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Enhanced sampling algorithms are indispensable when working with highly disconnected multimodal distributions. An important application of these is the conformational exploration of particular internal degrees of freedom of molecular systems. However, despite the existence of many commonly used enhanced sampling algorithms to explore these internal motions, they often rely on system-dependent parameters, which negatively impact efficiency and reproducibility. Here, we present fully adaptive simulated tempering (FAST), a variation of the irreversible simulated tempering algorithm, which continuously optimizes the number, parameters, and weights of intermediate distributions to achieve maximally fast traversal over a space defined by the change in a predefined thermodynamic control variable such as temperature or an alchemical smoothing parameter. This work builds on a number of previously published methods, such as sequential Monte Carlo, and introduces a novel parameter optimization procedure that can, in principle, be used in any expanded ensemble algorithms. This method is validated by being applied on a number of different molecular systems with high torsional kinetic barriers. We also consider two different soft-core potentials during the interpolation procedure and compare their performance. We conclude that FAST is a highly efficient algorithm, which improves simulation reproducibility and can be successfully used in a variety of settings with the same initial hyperparameters. [ABSTRACT FROM AUTHOR]

The evolution of microstructures and mechanical properties with tempering temperature of a novel 2.5 GPa grade ultra-high strength steel with synergistic precipitation strengthening was investigated. With increasing tempering temperature, the experimental steel initially progressed from ε-carbides to M3C and then to M2C, followed by further coarsening of the M2C carbides and β-NiAl. Concurrently, the martensite matrix gradually decomposed and austenitized. The ultimate tensile strength and yield strength initially increased and subsequently decreased with rising tempering temperature, reaching peak value at 460 and 470 °C, respectively. Conversely, the ductility and toughness initially decreased and then increased with rising tempering temperature, reaching a minimum at 440 °C. The increase in strength was attributed to the secondary hardening effects resulting from carbide evolution and the precipitation of β-NiAl. The subsequent decrease in strength was due to the recovery of martensite and coarsening of precipitates. The decrease in ductility and toughness was linked to the precipitation of M3C, while their subsequent increase was primarily attributed to the dissolution of M3C and an increase in the volume fraction of reverted austenite. The high dislocation density of martensite, the film of reverted austenite, nanoscale M2C carbides, and ultrafine β-NiAl obtained during tempering at 480 °C resulted in the optimal mechanical properties of the experimental steel. The strength contributions from M2C carbides and β-NiAl were 1081 and 597 MPa, respectively. [ABSTRACT FROM AUTHOR]

This study reports new observations from the fabrication of high-aspect-ratio hollow tubes of SS410 through wire-arc directed energy deposition (wire-arc DED) process. Characterisation work was performed on a single tube as a function of its build height. The maximum ultimate tensile strength (UTS) of 1372 MPa and maximum yield strength (YS) of 980 MPa were achieved in the middle region of the tube. The highest UTS in the middle was attributed to the low delta ferrite content. The reduction of delta ferrite was found to be linked with the repetitive heating and cooling. In contrast, the top and bottom sections exhibit a substantial presence of delta ferrite, indicating that the cyclic effects were not considerable. Nevertheless, the presence of significant ductility in the bottom region of the component indicated the occurrence of tempering effects. This observation is further supported by the lower levels of local strain observed using KAM mapping. Overall, this work proposes a novel fabrication method for producing hollow sections with superior strength and ductile properties. [ABSTRACT FROM AUTHOR]

Domain-specific hardware to solve computationally hard optimization problems has generated tremendous excitement. Here, we evaluate probabilistic bit (p-bit) based Ising Machines (IM) on the 3-Regular 3-Exclusive OR Satisfiability (3R3X), as a representative hard optimization problem. We first introduce a multiplexed architecture that emulates all-to-all network functionality while maintaining highly parallelized chromatic Gibbs sampling. We implement this architecture in a single Field-Programmable Gate Array (FPGA) and show that running the adaptive parallel tempering algorithm demonstrates competitive algorithmic and prefactor advantages over alternative IMs by D-Wave, Toshiba, and Fujitsu. We also implement higher-order interactions that lead to better prefactors without changing algorithmic scaling for the XORSAT problem. Even though FPGA implementations of p-bits are still not quite as fast as the best possible greedy algorithms accelerated on Graphics Processing Units (GPU), scaled magnetic versions of p-bit IMs could lead to orders of magnitude improvements over the state of the art for generic optimization. Specialized hardware for hard optimization is gaining traction. Here, the authors introduce a sparse, multiplexed, and reconfigurable p-bit Ising Machine on Field-Programmable Gate Arrays, using adaptive parallel tempering and higher-order interactions to achieve competitive performance on the 3-Regular 3-XORSAT problem. [ABSTRACT FROM AUTHOR]

Rachel Reeves's March 2024 Mais lecture was an exercise in tempering hope that Britain's threadbare public services would soon be restored to health. The message of restraint might prove to be early confirmation of Reeves's instinctive governing philosophy, but it also reflected the fact that she was called upon to speak in a context of epistemic injustice. Senior Labour politicians must always accept greater scrutiny of their fiscal policy pronouncements than their Conservative counterparts. Their statements are also susceptible to disinformation, such that what Labour's opponents insist its frontbench team are hiding from the electorate often gets treated as a more authentic account of its plans than anything Labour says for itself. [ABSTRACT FROM AUTHOR]

The carbide precipitation of H13 steel and its effect on hardness and friction and wear resistance are investigated by microstructure observation, phase analysis, and mechanical property test. Results show that the tempering hardness is mainly related to the content of secondary carbides. After solution treatment in the temperature range of 1040–1070 °C, quenching and tempering, with the increase of the solution temperature, the content of secondary carbides and hardness of H13 steel in the tempering microstructure increase first and then decrease, and both reach the maximum value when the solution temperature is 1060 °C. The change of hardness is consistent with that of the content of secondary carbides. When the solution temperature is 1040 °C, the wear mass loss of the tempered H13 steel is the least, which is 4.63 mg, indicating that its wear resistance is the best, and this is caused by the presence of more undissolved carbides in the tempering microstructure. With the increase of the solution temperature, the wear mass loss increases gradually, and the wear resistance decreases, which is mainly related to the content decrease of undissolved and secondary carbides and the content increase of residual austenite. [ABSTRACT FROM AUTHOR]

The tempering process is applied in marine 10Ni5CrMoV steel to study microstructure, and mechanical properties by multi‐scale characterizations, strain hardening behavior, and cryogenic toughening mechanism are further investigated. As the tempering temperature increases from 590 to 630 °C, the dislocation density decreases by up to 25% and the austenite volume fraction decreases by up to 35%. Additionally, the morphology of austenite changes from strip to bulk, which weakened the pinning effect on the laths, leading to a coarsened martensite and an increase in the equivalent grain size. Based on the modified Crussard–Jaoul analysis, the specimens at different tempering temperatures exhibit a single‐stage strain hardening behavior during plastic deformation. The increase in strength is attributed to the continuous transformation‐induced plasticity effect and the increasing dislocation density. Furthermore, high austenite volume fraction and the proportion of grain boundary misorientation above 45° promote the release of stress concentration and hinder the propagation of cracks. This results in an increase in the ductile–brittle transition temperature (DBTT) of the specimens from −105 to −135 °C. At a tempering temperature of 610 °C, the specimen demonstrates an outstanding balance between yield strength (868 MPa) and cryogenic toughness (DBTT of −135 °C). [ABSTRACT FROM AUTHOR]

Simultaneously enhancing the strength, plasticity, and toughness of metal materials has been a prominent research objective. In this study, the precipitation of nano-scale vanadium carbide particles at a lower tempering temperature is controlled to achieve three key benefits: reducing lattice distortion in bainitic ferrite, strengthening through precipitation, and enhancing the toughness of bainitic ferrite, while also maintaining the content and stability of retained austenite. The adopted procedure increases the comprehensive mechanical properties of steel by 17%. In particular, the room-temperature impact toughness is increased by 41%. This comprehensive microstructure optimization endows bainitic steel with an excellent combination of mechanical properties. [ABSTRACT FROM AUTHOR]

The T92 martensitic steel is utilized in thermal power plants because of its better mechanical properties, and it is needed to enhance the strength and improve the properties using heat treatment. The research aims to determine how the microstructure changes in T92 martensitic steel when normalized at 1000 °C for an hour and tempered at 760 °C for 2 hours using various cooling techniques, including air cooling, furnace cooling, and water quenching. It is characterized by using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) equipped with energy-dispersive X-ray spectroscopy (EDS), and optical microscopy (OM). Tensile strength, hardness and toughness measurements were also performed on the heat-treated T92 steel specimens. After tensile testing of heat-treated samples of T92 steel, the fracture surface was characterized using SEM to determine the fracture mode. The strength and hardness of T92 material increased with a normalizing of 1000 °C, whereas they decreased with a tempering of 760 °C. Compared to various material conditions, the tempering of 760 °C with air-cooled hold the tensile strength of 887 MPa, hardness of 267.42 HV and toughness of 135 J was shown to be the optimal combination. [ABSTRACT FROM AUTHOR]

In this study, the effect of the cold plastic deformation of a Bridgman anvil at room temperature on the hardness and wear resistance of X160CrMoV12 steel was investigated by utilizing the hardness test, X-ray diffraction (XRD), abrasive emery wear (AEMW) test, optical examination, and scanning electron microscopy (SEM). Three batches of samples were prepared for the experiment: I—as-hardened, II—after hardening with subsequent tempering at 600 °C for 1.5 h, and III—after hardening with subsequent plastic deformation. The hardening of the samples was performed at three temperatures: 1100 °C, 1150 °C, and 1200 °C. The highest content of retained austenite, as much as 69.02%, was observed during hardening at 1200 °C, while 17.36% and 38.14% were formed at lower temperatures, respectively. After tempering (Batch II), the content of residual austenite decreased proportionally by a factor of about seven for each hardening temperature. The effect of plastic deformation (Batch III) is observed, analyzing the hardness of the samples from the surface to the depth, reaching an average hardened depth of 0.08 mm. To evaluate the wear resistance, the surfaces of the three test batches were subjected to an abrasive emery wear test under a 5 N load. Hardened and plastically deformed samples showed higher wear resistance than hardened and tempered samples. The results confirmed that the optimal hardening temperature to achieve the maximum wear resistance of this steel is 1100 °C. [ABSTRACT FROM AUTHOR]

The residual stress in low‐carbon high‐strength steel is not effectively relaxed during alloy carbide precipitation but is fully relaxed during manganese partitioning. The specific microscopic mechanisms responsible for this observed phenomenon have yet to be fully elucidated. This study employs first‐principles calculations in conjunction with experiments to demonstrate that alloy carbide precipitation leads to the formation of dense dislocation tangles that hinder carbon diffusion and carbide precipitation. Conversely, manganese partitioning aids carbon diffusion by altering dislocation morphology while also causing plastic deformation. The simultaneous occurrence of partitioning plasticity and precipitation plasticity during manganese partitioning results in a more significant relaxation of residual stress compared to alloy carbides precipitation: The plasticity coefficient for alloy carbide precipitation is 1.303 × 10−5, while the plasticity coefficient for manganese partition is 2.691 × 10−5. During alloy carbide precipitation, the elastic strain energy decreases to 43.48% of its initial value, whereas it can be further reduced to 25.29% after manganese partitioning. [ABSTRACT FROM AUTHOR]

AISI 431 martensitic stainless steels (MSS) with 2.5 wt% Cu were fabricated via laser-directed energy deposition additive manufacturing followed by single-step tempering treatment. The influences of different tempering times at 600 °C on microstructure and mechanical properties of the as-deposited 431-2.5Cu MSS have been explored and analyzed. The as-deposited MSS specimen primarily consisted of lath martensite, austenite and M23C6 carbide. After the single-step tempering treatment at 600 °C, Cu-enriched (ԑ-Cu) nano-precipitates and reverse austenite can be formed and promoted by extending the tempering treatment. The microhardness, strength and elongation can be improved with increasing the tempering time up to 1.0 h, and subsequently reduced with the tempering time prolonging to 2.0 h. Compared to 431 MSS that requires a multiple-step heat treatment for excellent performance, the 431-2.5Cu MSS specimen presented superior tensile properties after single-step tempering at 600 °C for 1.0 h in the present work. The ultimate tensile strength (UTS), yield strength (YS) and elongation (EL) of one-hour tempered MSS were 1611 MPa, 1334 MPa and 16.3%, respectively. This study provides a quantitative theoretical reference and experimental basis for realizing short-process fabrication of the Cu-bearing MSS with high strength and ductility. [ABSTRACT FROM AUTHOR]

To achieve a balanced combination of high strength and high plasticity in high-strength low-alloy (HSLA) steel through a hot-rolling process, post-heat treatment is essential. The effects of post-roll air cooling and oil quenching and subsequent tempering treatment on the microstructure and mechanical properties of HSLA steels were investigated, and the relevant strengthening and toughening mechanisms were analyzed. The microstructure after hot rolling consists of fine martensite and/or bainite with a high density of internal dislocations and lattice defects. Grain boundary strengthening and dislocation strengthening are the main strengthening mechanisms. After tempering, the specimens' microstructures are dominated by tempered martensite, with fine carbides precipitated inside. The oil-quenched and tempered specimens exhibit tempering performance, with a yield strength (YS) of 1410.5 MPa, an ultimate tensile strength (UTS) of 1758.6 MPa, and an elongation of 15.02%, which realizes the optimization of the comprehensive performance of HSLA steel. [ABSTRACT FROM AUTHOR]

The effect of different tempering temperatures on the hydrogen embrittlement (HE) resistance of a V + Nb-microalloyed medium-carbon bolt steel was studied by slow strain rate tensile testing and hydrogen thermal analysis. The HE resistance represented by notch tensile strength σ bN of hydrogen-charged specimens increases with increasing tempering temperature T tem , and the σ bN of the in situ hydrogen-charged sample is considerably lower than that of the pre-hydrogen-charged sample. Both the diffusible hydrogen content C diff and hydrogen-trapping capability of the precipitates show a significant increase-decrease change trend with T temp. The ratio of C diff primarily trapped by nanoscale V-rich MC precipitates increases linearly with increasing T temp. The control of V-rich MC through suitable increasing T temp is vital for obtaining the best HE resistance although at the cost of decreased strength. It is thus suggested that a compromise between strength and HE resistance should be considered for the practical application of this type of steel. [Display omitted] • Effect of tempering temperature T tem on HE of V + Nb-added bolt steel was studied. • T tem has significant effect on both HE resistance and diffusible hydrogen content. • Control of V-rich MC carbide by T temp is vital for obtaining the best HE resistance. • Mechanisms for the variation of HE resistance with T tem were explored. • A compromise between strength and HE resistance should be considered. [ABSTRACT FROM AUTHOR]

This scientific article studies the chemical compositions, mechanical properties and abrasive wear of cast samples and machine parts made of 35GL steel. Presented are cast samples with a wear-resistant surfacing coating of the sormite PG-C27 type, obtained by casting using gasified models. The hardness and wear resistance of annealed, hardened and tempered steel samples and parts were tested in factory and laboratory conditions. Tests of finished parts for abrasive wear resistance were carried out in field conditions. Optimal heat treatment regimes with double-phase recrystallization were applied to parts of soil-cultivating machines. It has been proven that optimal heat treatment with double-phase recrystallization increases the hardness and wear resistance of cast samples and finished parts by 2-3 times. [ABSTRACT FROM AUTHOR]

This article presents the results of a study of the influence of extreme heating temperatures during the hardening of carbon and alloy tool steels on their structure formation. It has been shown that increasing the heating temperature for quenching above 1000°C causes the growth of austenite grains, while the dislocation density increases. In this case, a redistribution of carbon atoms occurs--some carbon atoms from the martensite lattice transfer to dislocations. [ABSTRACT FROM AUTHOR]

The article provides data on the influence of technological modes of liquid nitriding on the basic mechanical properties of high-speed steels such as hardness and bending strength. The possibility of increasing mechanical properties by changing the time and temperature of liquid nitriding depending on the final tempering temperatures has been shown. The possibility of shortening the technological cycle of heat treatment of high-speed steels by eliminating the threehour tempering while maintaining the hardness and strength of steels has been shown. [ABSTRACT FROM AUTHOR]

When analyzing weighted networks using spectral embedding, a judicious transformation of the edge weights may produce better results. To formalize this idea, we consider the asymptotic behavior of spectral embedding for different edge-weight representations, under a generic low rank model. We measure the quality of different embeddings—which can be on entirely different scales—by how easy it is to distinguish communities, in an information-theoretical sense. For common types of weighted graphs, such as count networks or p-value networks, we find that transformations such as tempering or thresholding can be highly beneficial, both in theory and in practice. for this article are available online. [ABSTRACT FROM AUTHOR]

Copyright of Materials & Technologies / Materiali in Tehnologije is the property of Institute of Metals & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Simultaneously enhancing the strength, plasticity, and toughness of metal materials has been a prominent research objective. In this study, the precipitation of nano-scale vanadium carbide particles at a lower tempering temperature is controlled to achieve three key benefits: reducing lattice distortion in bainitic ferrite, strengthening through precipitation, and enhancing the toughness of bainitic ferrite, while also maintaining the content and stability of retained austenite. The adopted procedure increases the comprehensive mechanical properties of steel by 17%. In particular, the room-temperature impact toughness is increased by 41%. This comprehensive microstructure optimization endows bainitic steel with an excellent combination of mechanical properties.

This study investigates the tempering behavior of bainite and martensite in a medium carbon, high silicon steel, with a focus on the microstructural evolution and the attainment of equilibrium, over a temperature range of 200–650 °C. The dissimilarities between the characteristics of the two initial microstructures, both comprising a C-saturated tetragonal ferrite matrix and retained austenite, are reflected in the differences observed in their evolution towards equilibrium as the tempering temperature increases. Therefore, while retained austenite plays a pivotal role in the bainitic microstructure, in the martensitic microstructure it is the ferritic matrix, which is highly dislocated and enriched in carbon, that plays a determinant role. The findings demonstrate that while both bainite and martensite can converge towards the same equilibrium state upon high-temperature tempering (600–650 °C), the pathway to this convergence is markedly different, with bainite exhibiting a slower transformation rate. This path to equilibrium has been characterised by means of high-resolution dilatometry, scanning electron microscopy and detailed X-ray diffraction analysis. This has provided a dynamic and detailed picture of the most relevant microstructural changes and tempering mechanisms in high silicon steels. It has also provided a foundation for tailoring heat treatment processes to optimise the mechanical properties of advanced bainitic and martensitic steels.

The effects of quenching and tempering temperatures on the microstructure and mechanical properties of super martensitic stainless steel (SMSS) 00Cr13Ni5Mo were studied. The SMSS after heat treatment is composed of martensite (α phase) and a small amount of austenite. When the quenching temperature is 930 °C, with the increase of tempering temperature, the enrichment of Ni in martensite leads to the formation of reverse austenite, the content of martensite phase decreases from 84.9 % to 80.0 %, and the average grain size increases from 23.23 μm to 27.07 μm. When tempering at 580 °C, the content of martensite phase decreases from 80.0 % to 83.7 % with the increase of quenching temperature. The average grain size increased from 25.23 μm to 35.01 μm. When the quenching temperature is 930 °C, the hardness and yield strength of SMSS decrease, and the hardness and yield strength are the highest at 530 °C, which are 275 HV and 873 MPa. The plasticity increases first and then decreases, and the plasticity is the best at 580 °C. The elongation and reduction of area were 22.87% and 71.41%. These changes in mechanical properties are mainly related to the content of martensite and reversed austenite in the microstructure. The tensile strength and elongation of SMSS under different process conditions were compared. The results show that when the quenching temperature is 930 °C and the tempering temperature is 580 °C, the comprehensive performance of SMSS is the best, reaching 18700 MPa•%. This value is 31% higher than that of forgings. Finally, the formation mechanism of reversed austenite was discussed, and the strengthening model of SMSS 00Cr13Ni5Mo was established.

A system associated with several number of weak interactions supports numerous number of stable structures within a narrow range of energy. Often, a deterministic search method fails to locate the global minimum geometry as well as important local minimum isomers for such systems. Therefore, in this work, the stochastic search technique, namely parallel tempering, has been executed on the quantum chemical surface of the CNO(‐)(H2O)n system for n=1–8 to generate global minimum as well as several number of local minimum isomers. IR spectrum can act as the fingerprint property for such system to be identified. Thus, IR spectroscopic features have also been included in this work. Vertical detachment energy has also been calculated to obtain clear information about number of water molecules in several spheres around the central anion. In addition, in a real experimental scenario, not only the global but also the local minimum isomers play an important role in determining the average value of a particular physically observable property. Therefore, the relative conformational populations have been determined for all the evaluated structures for the temperature range between 20K and 400K. Further to understand the phase change behavior, the configurational heat capacities have also been calculated for different sizes. [ABSTRACT FROM AUTHOR]

Low carbon medium manganese steel with chromium and molybdenum addition (4MnCM), alongside a control group without these additions (4Mn), was developed. The quenching (860 °C) and tempering (620 °C) heat treatment process was applied to both steel groups. The influence of Cr and Mo on the microstructure evolution and mechanical properties was examined. The findings revealed that, the low−temperature impact energy values (KV2) of 4MnCM at −60 and −84 °C were enhanced by 104 and 107 J, in comparison to 4Mn. The yield and tensile strength saw an increase of 100 MPa. The higher low-temperature toughness of 4MnCM is attributed, on one hand, to the addition of Cr and Mo, which inhibiting deformation twinning through enhances the stacking fault energy (SFE) of reversed austenite. On the other hand, it is due to the absence of coarse ε−martensite (ε−m) along the crack propagation path. Additionally, the phase transformation of reversed austenite occurs at the crack nucleation stage during the impact process of both steels, which helps alleviate stress concentration and increases the energy required for crack formation. The primary reason for the higher strength of 4MnCM lies in the significant enhancement of precipitation strengthening effects through the precipitation of M6C, M23C6 and Nb/TiC co-precipitation with M6C.

In order to improve the drying quality of rice, Indica and japonica hybrid rice were taken as the object and evaluated by waist burst rate, head rice rate, energy consumption and drying time in this experiment. Single factor and response surface analysis were combined to optimize the drying process. The effects of variable temperature-tempering drying on proteins structure and thermal properties of indica and japonica hybrid rice were investigated by differential scanning calorimetry. Fourier infrared spectroscopy and fluorescence spectroscopy. The results showed variable temperature-tempering drying (temperature range 30~60 ℃) that under the conditions of temperature rise 5 ℃, wind speed 1 m/s and tempering ratio 0.6, the rice could be kept in the glassy state, and the waistband burst rate and head rice rate after drying were 79.89% lower and 39.54% higher than those in the constant temperature group (60 ℃), respectively. Under these conditions, the polarity of rice proteins decreased and intermolecular aggregation occured, which improved the thermal stability of rice proteins, and the α-helix content increased from 16.21% to 17.64%. Scanning electron microscope results showed that the surface structure of protein was not significantly affected by variable temperature-tempering drying. The experiment explored and verified the drying mechanism of hybrid rice with variable temperature-tempering drying, which would provide a theoretical and practical reference for the research of high quality drying of hybrid rice.

The effect of the structure on the strength and crack resistance of maraging steel is studied in cyclic loading. The impact of dispersity of intermetallide precipitates formed in the course of tempering on the cyclic crack resistance is considered. The paper discusses the variation in the characteristics of cyclic crack resistance of the studied steel depending on the elements of its microstructure and on the modes of quenching and subsequent tempering. It is shown that in a maraging steel with a coarse-grained structure, there is a high level of near-threshold cyclic crack resistance, probably related with the ratio of the number of loading cycles and the size of the cyclic plastic deformation zone. [ABSTRACT FROM AUTHOR]

When a suitable balance of hardness, strength, and toughness is required in civil engineering and construction, wear-resistant medium carbon steels are frequently utilized. The ability to resist plastic deformation brought on by stress or abrasion is measured by hardness. High hardness materials are typically more brittle and prone to fracture but also stronger and more resistant to corrosion. A double-quenching procedure was used in the current investigation and contrasted with the traditional single-quenching process. Additionally, a variety of cooling media are used during quenching treatments. The results demonstrate that distilled water is the most effective cooling medium to cool the models in the heat treatment of medium carbon steels because it is free of salts, suspended particles, and metal contaminants. The results show that the hardness increased following the first quenching and tempering by 37.5% above the hardness value predicted by the original model, and it increased once more following the second quenching and tempering by 10% over the hardness value following the first heat-treatment. The previous austenite grain limits and the high-angle beam limits are the main factors that give a share in to the increased hardness, and the main elements that affect how effectively they function are the high slip transmission factor and the high spacing angle between slip levels. [ABSTRACT FROM AUTHOR]

Existing optimization research on the crankshaft heat treatment process is mostly based on one-sided considerations, and less consideration is given to the matching of multiple process parameters, leading to irrational designs of heat treatment. To address this problem, this work investigates the influence mechanisms of cooling speed, tempering temperature, and holding time on the performance evaluation indexes of the straightness, residual stress, and martensite content of a crankshaft based on the response surface method. The results showed that the order of influence of these three different process parameters on the performance evaluation index was cooling speed > holding time > tempering temperature, and the order of influence on the performance evaluation indexes under multifactorial process parameters was cooling speed–holding time > cooling speed–tempering temperature > holding time–tempering temperature. The optimal process parameters were a cooling speed of 1.4 times the cooling oil, a tempering temperature of 555 °C, and a holding time of 6 h, with the straightness of the crankshaft reduced by 9.9%, the surface stress increased by 6.7%, and the martensitic content increased by 7.2% after the process optimization. This work can provide new clues for optimizing the heat treatment process parameters of crankshafts. [ABSTRACT FROM AUTHOR]

AbstractWheat-based foods has emerged as another potential vehicle for foodborne illness in humans. The recent occurrence of recalls involving wheat-based foods requires a full understanding of how these pathogens thrive in these food products and developing potential intervention strategies to address pathogen contamination. This manuscript is the second of a two-part review covering the status of the food safety of wheat-based products. In this manuscript, available information on the survival of enteric foodborne pathogens, food safety issues, and potential pathogen reduction steps on wheat-based foods were reviewed. Shiga toxin-producing E. coli and Salmonella are capable of surviving in wheat flours and grains for extended periods (≤ 2 years). Based on the food safety issues linked to wheat flour, the main enteric pathogens of concern are STEC (O157, O121, O26, and O103) and Salmonella. Diverse interventions such as tempering treatments, thermal treatments, and non-thermal technologies all effectively reduced the pathogenic loads of wheat grains and wheat flours (2 to 6 log CFU/g reduction). Addressing pathogen contamination of wheat-based foods is a major concern for the milling industry. Future studies could be focused on improving pathogen reduction performance and validating their effects against diverse product and process conditions. [ABSTRACT FROM AUTHOR]

The microstructure and mechanical properties of marine 10Ni5CrMoV steel are systematically investigated at tempering temperatures ranging from 630 to 670 °C. With increasing tempering temperature, several key parameters exhibit notable changes: the volume fraction of reversed austenite decreases from 17.36% to 13.39%. The equivalent grain size increases from 0.91 to 1.09 μm. The equivalent diameter of precipitates increases from 59 to 79 nm. The dislocation density decreases from 0.82 × 10−15 to 0.51 × 10−15 m−2. As the tempering temperature increases, the pinning effect of precipitates on dislocations and martensite laths decreases. This leads to reductions in both dislocation strengthening and precipitation strengthening mechanisms. Consequently, the yield strength of the specimen decreases from 876 to 683 MPa. The increase in the ductile‐brittle transition temperature of the specimens from −116 to −95 °C can be attributed to several factors. First, the increase in precipitate size reduces the critical nucleation stress of cleavage cracks and promotes the nucleation of such cracks. Additionally, the decrease in dislocation density mobility leads to a reduction in the dimple nucleation rate, thereby diminishing the role of dimples in hindering crack propagation. [ABSTRACT FROM AUTHOR]

Seeding (SD) is a chocolate pre-crystallization technique (PT) that serves as a more efficient alternative to conventional tempering (CT), yielding equivalent characteristics within the category of well-tempered chocolate. However, variability in macroscopic quality attributes may persist. This study aims to discern variations among well-tempered chocolates obtained through various configurations of PTs: CT, SD, and a combination of both (CS), focusing on changes during pre-crystallization, solidification, and subsequent storage at 20 °C. The increased yield stress (> 1.2 Pa) of pre-crystallized chocolate in comparison to non-tempered chocolate, melting peak alignment with the β V cocoa butter (CB) polymorph (29–34 °C) after 6-h storage and fat-bloom resistance up to 9 months, affirm the successful integration of different PTs within the well-tempered chocolate category. However, distinct melt⟶2L⟶3L lamellar packing transition mechanisms for each PT were identified in the first hour of solidification through synchrotron-assisted time-resolved X-ray scattering. Varied polymorphic transition and microstructural growth kinetics were also observed over 28 days of storage, as indicated by melting profiles. CS chocolate exhibited limited transition, remaining stable as β V . In contrast, CT and SD underwent rapid microstructural growth with an indication of a small fraction of CB polymorph transitioning to the undesirable β VI CB polymorph (> 34 °C), linked to fat bloom development. Surface topography observation through accelerated shelf-life test at 26 °C over 9 months marked the link with CB crystal microstructural growth, with fat bloom occurring faster on SD chocolate, then CT chocolate, and finally the CS chocolate. These findings highlight the potential to tailor crystallization kinetics by adapting PT to achieve improved product qualities, such as extended fat-bloom resistance or accelerated solidification while remaining within the well-tempered category. [ABSTRACT FROM AUTHOR]

Copyright of Bearing is the property of Bearing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Steel Pipe is the property of Steel Pipe Magazine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The present research work deals with the results of influence of different heat treatment conditions on the microstructure stability and mechanical properties of high-chromium X10CrMoVNNB9-1(P91) cast and forged (C&F) P91 steel. The C&F P91 steel was subjected to various tempering condition in the temperature range of 350–760 °C and tempering time of 2 h, after the normalizing at 1040 °C for 40 min. The steel was also subjected to furnace cooled and water quenched heat treatment. Tempering at 650 and 760 °C produced the fully tempered lath martensitic structure with M23C6, M7C3, M3C and MX precipitates along the prior austenite grain boundaries, lath boundaries and matrix region. Tempering at 350 and 1000 °C produced the partially tempered columnar laths and untempered columnar laths martensite, respectively. The tempering time was also varied from 2 to 8 h for fixed tempering temperature of 760 °C. The optimum microstructure evolution was obtained for 6 h of tempering at 760 °C that led to improved mechanical properties. [ABSTRACT FROM AUTHOR]

Breaking trade-off relationship between strength and ductility in steels has been a perpetual topic, since researchers have been pursuing more energy and resource-efficient manner to use steels. In this study, rolling, tempering and inter-critical annealing were innovatively combined to obtain high strength-high ductility combination in Fe-4Mn-4Ni-3Al-0.1C steel. The process referred as multi-step inter-critical annealing (MIA) was designed to accomplish the following objectives: (a) a stretched lamellar-shaped grain structure resulting from rolling at nonrecrystallization region of austenite, (b) Mn/C-heterogeneous austenite inherited from carbides formed during tempering. Therein, Mn/C-depleted austenite areas originated from ferrite; meanwhile, Mn/C-enriched austenite areas originated from the carbide dissolution, (c) transformation hardening of Mn/C-depleted austenite area during cooling in the inter-critical annealing, (d) stress relaxation of Mn-enriched austenite area retained as retained austenite at room temperature. The specimen achieved excellent mechanical response through the optimized MIA process (tempering at 400°C for 3 hours, then inter-critical annealing at 765°C for 40 minutes). The obtained microstructure was composed of alternating lamellae of bainite and a special annealed martensite on microscale, with the latter consisting of secondary martensite and retained austenite films on nanoscale. The yield strength and total elongation of the steel were increased from 858 MPa and 12% in direct inter-critical annealing process to 1011 MPa and 32% in MIA respectively. The modified Crussard-Jaoul analyses were used to evaluate the deformation behavior of the steels. Due to lots of bainite formation, a relatively high initial strain hardening exponent (0.72m-1) was observed for the DIA steels. While lower initial strain hardening rate (0.32m-1) and more stages of work hardening because of increasing stable austenite and secondary martensite in the MIA steels ensured the excellent strength-ductility combinations. [ABSTRACT FROM AUTHOR]

Low-carbon bainitic steels are known for their excellent combination of strength and toughness, making them suitable for various industrial applications. Understanding the tempering behavior of these steels is crucial for optimizing their mechanical properties through heat treatment. This study presents predictive models for tempering behavior based on empirical data, which is fundamental for understanding the thermal stability and transformation kinetics of the steel. Through integrated tempering parameters, we established predictive models that integrate tempering temperature and time, yielding a robust framework for predicting hardness. The equivalent tempering kinetic curves and nomographs plotted in this study allow for the direct determination of hardness under various tempering conditions, facilitating the optimization of tempering parameters. The nomogram approach provides a practical method for adjusting tempering parameters to achieve desired mechanical properties efficiently. The accuracy of the predictive models was validated through statistical tests, demonstrating a high correlation between predicted and experimental values. [ABSTRACT FROM AUTHOR]

Copyright of Metal Working (1674-165X) is the property of Metal Working Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

While it is well known today that J.S. Bach’s The Well-Tempered Clavier (WTC) was not composed with equal temperament in mind, it is unknown exactly which, if any, well temperament Bach had intended for the work. While equal temperament produces 12 uniform intervals of each type, other systems of well temperament slightly stretch and compress the size of various fifths, resulting in alterations to other intervals. A number of competing hypotheses have been published as to which temperament Bach intended, or whether he intended a specific temperament at all. While we do not have a definitive historical answer as to Bach’s preference of temperament in this work, this paper applies corpus methodologies to compare these systems. This paper develops and utilises Detuning-Emphasis Correlation (DEC): the relationship between scale-degree pairs' deviation from just intonation and their frequency of use. Frequency of use is compared to a ‘baseline’ frequency, found by averaging a scale degree pair’s prevalence across the corpus. This paper analyses the 48 fugues of Bach’s WTC by computing DECs for selected well temperaments (Werckmeister III, Bach-Lehman, Niedhardt, Vallotti, and Young), aiming to find a significant negative DEC for some temperament. While no temperament was found to fit the WTC in this way, strong correlations between these well temperaments indicated that the work would highlight similar affects for the various keys regardless of which (non-equal) well temperament is used to realise this work. [ABSTRACT FROM AUTHOR]

Copyright of Science & Technology of Food Industry is the property of Science & Technology of Food Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

During low‐temperature tempering of wear‐resistant steel, ε‐carbide precipitation can effectively relax residual stress, and its microscopic mechanism is currently unclear. To reveal the stress relaxation mechanism during ε‐carbide precipitation, density functional theory calculations are combined with experiments to explore the ε‐carbide growth behavior and the stress evolution. The results show that ε‐carbide precipitation includes two stages: ε‐precursor formation and ε‐carbide nucleation, and ε‐carbide is in situ nucleated from ε‐precursor matrix. The precipitation‐induced stress relaxation behavior mainly occurs in the early stage of ε‐precursor formation and ε‐carbide nucleation. The early stage of ε‐precursor formation and ε‐carbide precipitation can relax the residual stress to 35.73% and 27.07%, respectively. [ABSTRACT FROM AUTHOR]

The purpose of this article is to assess the effect of a writing framework model for pedagogical reflection in a sample of elementary school teachers who took part in a lifelong learning program. To do so, a combined research design was carried out, implementing, on the one hand, inferential and multivariable statistical techniques to determine the tempering effect of feedback on the performance of written reflection and, on the other hand, content analysis of the teachers' written production to identify their development of pedagogical reflection. He results reveal that encouraging this reflection in teachers' writing allows them to develop a more in-depth assessment and analysis of their own practices, which is evidenced by the use of more detailed explanations and arguments and the precision of the terminological use of specific concepts. [ABSTRACT FROM AUTHOR]

Silicon carbide was employed as a source of silicon and carbon to produce sintered silicon steels, offering the advantages of silicon addition. This work explored the effects of low SiC contents of 1.0 and 2.0 wt.% on as-sintered and as-tempered microstructures and mechanical properties of sintered silicon steels. The experimental sintered steels were produced from mixtures of pre-alloyed Fe-1.50Mo and SiC powder. The mixtures were compacted to tensile bars, sintered at 1553 K for 2.7 ks, and cooled at 9.0 K/s with N2. Sintered specimens were tempered at 873 K and held for different times. The microstructures and mechanical properties of the sintered and tempered specimens were characterized. It was revealed that the sintered silicon-bearing steels showed low temperature phase transformations under cooling at 9.0 K/s. The sintered steel produced by 1.0 wt.% SiC addition had degenerate upper bainite microstructure and its tempered microstructure was upper bainite. The sintered steel produced by 2.0 wt.% SiC addition had a microstructure consisting of bainitic-ferrite plates, martensite plates, and austenite blocks. Its tempered microstructure was upper bainite. The tempered microstructures resembled those of sintered Si-free Fe-Mo-C steels. Tempered specimens exhibited tensile strength higher but elongation lower than sintered ones attributed to carbide precipitation strengthening. [ABSTRACT FROM AUTHOR]

Investigation on the effects of Zr and quenching and tempering processes on the microstructure and properties of high-strength Ti-Mo microalloyed steel using SEM, TEM, mechanical property testing, and First-principles calculations. The results show that within the tempering temperature range of 550–650 °C, the microstructures of Ti-Mo microalloyed steel and Ti-Zr-Mo microalloyed steel consist of ultra-low carbon martensite and carbides. Specifically, the strength of Ti-Mo microalloyed steel initially increases and then decreases with the increase in tempering temperature, while the strength of Ti-Zr-Mo microalloyed steel increases with the increase in tempering temperature. During tempering, the addition of Zr element affects the diffusion of C element, delaying the martensitic tempering transformation process, and slowing down the nucleation, growth, and coarsening processes of alloy carbides. First-principles calculation results indicate that ZrC preferentially forms during tempering, resulting in a certain sequential gradient of precipitated microalloy carbides, thereby enhancing the tempering stability of microalloyed steel. Compared to Ti-Mo steel, Ti-Zr-Mo steel exhibits narrower lath martensite width and finer dispersed precipitation phases after tempering at 600 °C and 650 °C. [ABSTRACT FROM AUTHOR]

The aim of this work is to study the phase transformations, microstructures, and mechanical properties of martensitic stainless steel (MSS) 410 deposits produced by laser powder-directed energy deposition (LP-DED) additive manufacturing. The LP-DED MSS 410 deposits underwent post-heat treatment, which included austenitizing at 980 °C for 3 h, followed by different tempering treatments at the temperatures of 250, 600, and 750 °C for 5 h, respectively. The analyses of phase transformations and microstructural evolutions of LP-DED MSS 410 were carried out using X-ray diffraction, SEM-EDS, and EBSD. Vickers hardness and tensile strength properties were also measured to analyze the effects of the different tempering heat treatments. It revealed that the as-built MSS 410 has very fine lath martensite, high hardness of about 480 HV1.0, and tensile strength of about 1280 MPa, but elongation was much lower than the post-heat-treated ones. Precipitations of chromium carbide (Cr23C6) were most commonly observed at the grain boundaries and the entire matrix at the tempering temperatures of 600 °C and 750 °C. In general, the tensile strength decreased from 1381 MPa to 688 MPa as tempering temperatures increased to 750 °C from 250 °C. Additionally, as the tempering temperature increased, the chromium carbide and tempered martensite structures became coarser. [ABSTRACT FROM AUTHOR]

Two low-alloy quenched-tempered steels (#1 steel and #2 steel) are designed and comparatively studied to achieve ultrahigh yield strength (above 2000 MPa) at relatively low material and process costs. #1 steel and #2 steel have chemical compositions (wt pct) of 0.62 C, 1.62 Si, 0.78 Mn, 1.05 Cr, and 0.18 V and 0.55 C, 1.74 Si, 0.67 Mn, 1.12 Cr, 0.14 V, 0.21 Ni, and 0.20 Mo, respectively. The two steels are heated to 950 °C for 30 minutes, oil quenched, tempered at 240 to 440 °C for 90 minutes and water cooled. Under the same heat treatment parameters, the two steels have basically the same strength (tensile strength 2100 to 2400 MPa; yield strength 1950 to 2100 MPa). Interestingly, as the tempering temperature decreases from 440 °C to 240 °C, the elongation of #1 steel decreases from 10.7 to 1.8 pct, but that of #2 steel is quite stable at ~ 10 pct. #2 Steel has a high tempering resistance, and χ-carbide precipitation of #2 steel is significantly suppressed during tempering. Moreover, when tempering at 240 to 400 °C, the austenite volume fraction of #2 steel is higher than that in the quenched state. The reduction in carbide precipitation contributes to carbon segregation at martensite lath boundaries and other locations, and it may promote the formation of reversed austenite during tempering, which is revealed by 3D atom probe tomography (APT). The excellent mechanical properties of #2 steel are mainly related to the reversed austenite, the fine-grained microstructure of the martensite matrix and the reduced carbides acting as crack initiation sites. [ABSTRACT FROM AUTHOR]

The main objectives of this recent study were; to relate roller position, roller gap and tempering enzymes to flour yield and characteristics. Wet milling of wheat (Triticum aestivum, L.) represented by Australian commercial grade was included. Added enzymes were two levels; control, and hemicellulase + xylanase + fungal α-amylase. Results showed that, the highest significant values of wet gluten (%) were obtained with dull-to-sharp position and G1 gap and the addition of E1 (hemicellulase + xylanase + fungal α- amylase) enzyme (36.12%), while, the highest significant value of falling number (sec.) was obtained with dull-to-dull position and G2 gap and no addition (E0) of enzymes (726.0 sec.). The highest significant values of extraction rate (%) was obtained with dull-to-dull and G3 gap and the addition of E1 (hemicellulase + xylanase + fungal α- amylase) enzyme (80.00%). The highest significant values of (FQN) were obtained with the combination of dull-to-sharp with G2 gap and the addition of E1 (hemicellulase + xylanase + fungal α- amylase) enzyme (369.0 mm). Meanwhile, the highest significant values of curve configuration ratio were presented with the combination of dull-to-dull with G3 gap and no addition of enzyme (0.890). The highest significant values of loaf weight were obtained with dull-to-dull position, G3 gap, and the addition of no enzyme (231.0 and 231.5 g, respectively). Also, the highest significant loaf volume (cm³) was presented with dull-to-dull or dull-to-sharp, G3 gap and adding (hemicellulase + xylanase + fungal α- amylase) enzymes (1475.0 or 1467.5 cm³, respectively). The highest significant values of specific volume (cm³/g) were presented with dull-to-dull position and adding (hemicellulase + xylanase + fungal α- amylase) enzymes and any of the studied gaps. The highest significant values of peak force were presented with the combination of dull-to-sharp position and five-days of storage time with addition or no addition of enzymes (759.9 and 765.3 g, respectively). Best-fit equations that related grain properties of Australian wheat grade, roller position, roller gap and tempering added enzyme to the out-come might be summarized as follow: [ABSTRACT FROM AUTHOR]

This study aims to develop a flow rule for evaluating the relaxation and redistribution of residual stresses during the post-weld heat treatment (PWHT) of hydroelectric runners made from low-carbon martensitic stainless steel (13Cr-4Ni composition). During the PWHT, austenite reforms in the filler metal and surrounding areas of the base metal near welded joints. The evolving inelastic strain rate with reformed austenite led to defining two distinct flow rules in the pure martensitic (α′) and austenitic (γ) phases. A linear rule of mixture was then applied to assess global effective stress based on the inelastic strain rate and current austenite fraction during the PWHT. A unified constitutive model incorporating drag stress and back stress, evolving with creep and plastic deformation mechanisms during the PWHT, described the stress–strain behavior. To validate this analysis, a third flow rule was determined in the 18% tempered austenitic microstructure, compared with the rule of mixture's effective stress contribution from each phase on the inelastic strain rate. Isothermal constant strain rate tests in stabilized crystalline microstructures evaluated constants specific to their respective flow rules. This study demonstrates the stability of reformed austenite at elevated temperatures during slow cooling and its significant influence on the mechanical properties of 13Cr-4Ni steels. The effectiveness of estimating yield stress using the rule of mixture based on individual phase behaviors is also confirmed. [ABSTRACT FROM AUTHOR]

Tempering, the controlled addition of water to wheat before milling, is an essential step for maximizing flour yield in the milling industry. However, the limited availability of water significantly impacts moisture migration within the kernels, consequently influencing their breakage behavior. This study investigates the effects of tempering time (3, 6, 9, and 12 h) and moisture content (14%, 16% and 18%) on the moisture diffusivity and compressibility characteristics of single wheat kernels from hard red winter (HRW) and hard red spring (HRS) varieties. Uniaxial compression tests revealed a significant influence of tempering time on the viscoelastic properties of the kernels. Tempering moisture content significantly decreased elasticity of HRW kernels from 155. 8 MPa to 89.2 MPa, whereas for HRS the decrease was from 192.2 MPa to 115.0 MPa. Higher tempering moistures decreased the elastic work from 8.8 to 5.4 N. mm while increased the plastic work to 1. 92 N.mm, suggesting improved flour extraction. Compressibility followed first order kinetics, with rate constants ranging from 0.002 to 0.0057 h− 1 for HRS and from 0.0026 to 0.0066 h− 1 for HRW. Kernel diffusivity exhibited variations with tempering moisture for both the kernels, although these differences were not statistically significant. These findings provide insights into the interaction between tempering conditions and kernel properties, for optimizing the tempering processes to enhance flour extraction efficiency. [ABSTRACT FROM AUTHOR]

The scope of this study is to enhance the performance of AISI 1045 steel for demanding marine applications like connecting rods, axles, and wear-resistant components. Traditional heat treatment methods, including boriding, surface induction hardening, and tempering, improve the steel’s surface hardness. Additionally, the Tungsten Inert Gas (TIG) coating process develops a novel Cr- TiB2 composite coating on the heat-treated AISI 1045 stainless steel. The investigation explores the influence of varying TiB2 content (10%, 20%, and 30%) on the mechanical properties of AISI 1045 steel. Microhardness and tensile characteristics are analyzed, considering the impact of TiB2 percentage. Surface morphology and interfacial bonding are examined using Scanning Electron Microscope (SEM) and Energy Dispersive X-Ray Analysis (EDAX). Results reveal notable improvements, including a 2.65 times increase in microhardness compared to untreated AISI 1045 steel, uniform TiB2 distribution, and a crack-free coating. The addition of TiB2 particles in the Cr- TiB2 composite coating enhances microhardness. Improved mechanical properties are attributed to surface treatments, incorporation of hard and wear-resistant materials (Cr and TiB2) in the composite coating, microstructure modifications, and crack prevention, collectively resulting in increased hardness, wear resistance, and durability. Furthermore, this study introduces a novel hybrid Deep Neural Network-based Sandpiper Optimization Algorithm (DNN-SOA) for predicting experimental outcomes with superior accuracy. This research not only enhances the understanding of the coated steel’s mechanical properties but also presents an innovative predictive model for future material engineering applications, demonstrating the significance of advanced heat treatment and a novel composite coating in improving AISI 1045 steel performance. [ABSTRACT FROM AUTHOR]