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The microstructure and texture of an AlFeMn alloy were studied under different intermediate annealing processes, and the changes in microhardness during cold rolling were analyzed. After annealing at 420 °C with a slow heating rate, the alloy showed a high number of small dispersed particles and recrystallization textures dominated by R texture, with deformation textures of 23.5%. Annealing at 610 °C with a rapid heating rate resulted in a significant decrease in the number of small-sized particles and an increase in recrystallization texture contents, with CubeND being the majority. The deformation texture contents decreased to 14.9%. The electrical conductivity of the 420 °C annealed sheet was higher than before annealing, whereas the sheet annealed at 610 °C showed a decrease in electrical conductivity after annealing. This indicated that annealing at 610 °C led to a higher degree of recrystallization and the development of Cube/CubeND due to the dissolution of dispersed particles. During the subsequent cold rolling process, the microhardness of both annealed sheets initially increased and then decreased. However, the microhardness of the 420 °C annealed sheet with varying cold rolling reductions consistently remained lower than that of the 610 °C annealed sheet, as was the cold rolling reduction corresponding to the peak microhardness. The results showed that the precipitation at 420 °C facilitated work softening, while the dissolution at 610 °C promoted work hardening. [ABSTRACT FROM AUTHOR]

The microstructure evolution during the cold rolling and subsequent annealing of Alloy 800H was investigated. Two distinct rolling methods, unidirectional rolling and cross-rolling, were introduced. Cracks were observed in the cross-rolled plates, while such cracks did not appear in the unidirectionally rolled plates, which indicated better ductility during the unidirectional rolling process. The difference between the two different rolling methods was explained by the evolution of Schmit factors during the deformation. A higher volume fraction of large, deformed grains was observed in the cross-rolled plates than in the unidirectionally rolled plates. Abnormal grain growth was observed in the cross-rolled specimens after annealing while no abnormal grain growth was seen in the unidirectionally rolled ones. In addition, the recrystallization occurred faster in plates from unidirectional rolling than from cross-rolling. [ABSTRACT FROM AUTHOR]

Rolling is one of the most important processes in the metallurgical industry due to its versatility. Despite its inherent advantages, design and manufacturing by rolling still rely on trial-and-error-based optimizations, which reduces its efficiency. To minimize the cost and time spent on the development of new rolling schedules, various analytical and numerical methods have been used in recent years. Among other alternatives, simulations based on the finite element method (FEM) are the most widely used. This allows for the analysis of the feasibility of new rolling schedules considering metal alloys with different characteristics, process conditions, or the creation of new operations, as well as the optimization of existing ones. This paper presents a literature review including the latest developments in the field of numerical simulation of rolling processes, which have been classified according to the type of rolling into the following categories: flat rolling, shape rolling, ring rolling, cross-wedge rolling, skew rolling, and tube piercing. [ABSTRACT FROM AUTHOR]

One challenge in developing new materials is solid metal-induced embrittlement, where the fracture stress or ductility of the metal decreases upon contact with another metal surface. Materials such as aluminium demand precise temperature control for optimal results, often requiring specialized equipment. Strengthening aluminium alloys often involves cold working techniques like wire drawing or cold rolling. By combining methods such as cold working, heat treatment, and most especially alloying, the mechanical properties of aluminium alloys can be optimized. To address these concerns, an experimental study investigated the nanomechanical response of an alloy developed for anti-corrosion and structural applications. Corrosion behaviour was evaluated in a 3.65 wt% NaCl solution using a potentiostat/galvanostat, while tribological performance was assessed using a reciprocating sliding tribometer. Microhardness properties were studied using a Vickers microindenter, and thermal stability was examined using a thermo-gravimetric analyzer. Structural modifications were analysed using SEM/EDX and X-ray diffractometer (XRD). Results showed that the HEA (high entropy alloy) 17 sample exhibited outstanding corrosion resistance, with a corrosion rate (CR) of 0.0639 mm/year and corrosion current density (jcorr) of 5.500E−06 A/cm2. All HEA samples displayed high wear rates and worn track sections compared to CONTROL 2. The HEA 16 and HEA 18 samples demonstrated notably high Vickers hardness of 534.50 µN/mm2 and 533.48 µN/mm2, respectively. Despite its high copper content, the CONTROL 1 sample did not exhibit comparable hardness. SEM images revealed refined microstructures and distinct outer morphologies in the examined samples. [ABSTRACT FROM AUTHOR]

High-entropy alloys (HEAs) with a face-centered cubic (FCC) structure have recently received significant attention due to their outstanding ductility and fracture toughness. In this study, the effects of Ti addition and annealing on the microstructures and mechanical properties of CoCrFeMnNi HEAs were investigated. Two CoCrFeMnNiTix (x = 0 and 0.2, named Ti-0 and Ti-0.2) HEAs were prepared by arc melting, followed by homogenization, cold rolling and annealing at 800 °C and 900 °C, respectively, for 1 h. The microstructure evolution, crystallographic texture and mechanical properties were studied. It was found that the Ti-0 alloy exhibited a single-phase FCC solid solution, while Cr-rich σ phase and (Ni, Co)3Ti η phase precipitated in the Ti-0.2 alloy after annealing. With the precipitation of the hard yet brittle σ and η phases, the yield strength and hardness of Ti-0.2 alloy increased significantly but with the sacrifice in the tensile elongation. The contributions of intrinsic strength, solid solution, grain size and precipitation strengthenings to the tensile yield strength were calculated and compared with measurements. Both grain boundary strengthening and precipitation strengthening were the main strengthening mechanisms for the Ti-doped CoCrFeMnNi HEAs. [ABSTRACT FROM AUTHOR]

Medium-entropy alloys (MEAs) have attracted considerable attention in recent decades due to their exceptional material properties and design flexibility. In this study, lightweight and non-equiatomic MEAs with low density (~5 g/cm3), high strength (yield strength: 1200 MPa), and high ductility (plastic deformation: ≧10%) were explored. We fine-tuned a previously developed Ti-rich MEA by microalloying it with small amounts of Ni (reducing the atomic radius and increasing the elastic modulus) through solid solution strengthening to achieve a series of MEAs with enhanced mechanical properties. Among the prepared MEAs, Ti65Ni1 and Ti65Ni3 exhibited optimal properties in terms of the balance between strength and ductility. Furthermore, the Ti65Ni3 MEA was subjected to thermo-mechanical treatment (TMT) followed by cold rolling 70% (CR70) and cold rolling 85% (CR85). Subsequently, the processed samples were rapidly annealed at 743 °C, 770 °C, 817 °C, and 889 °C at a heating rate of 15 °C/s. X-ray diffraction analysis revealed that the MEA could retain its single-body-centered cubic solid solution structure after TMT. Additionally, the tensile testing results revealed that increasing the annealing temperature led to a decrease in yield strength and an increase in ductility. Notably, the Ti65Ni3 MEA sample that was subjected to CR70 and CR85 processing and annealed for 30 s exhibited high yield strength (>1250 MPa) and ductility (>13%). In particular, the Ti65Ni3 MEA subjected to CR85 exhibited a specific yield strength of 264 MPa·cm3/g, specific tensile strength of 300 MPa·cm3/g, and ductility of >13%. [ABSTRACT FROM AUTHOR]

Preparation of a titanium foil with weak anisotropy is of great significance for the development of bipolar plate materials for hydrogen fuel cell. However, the titanium foil obtained by rolling deformation often suffer from a severe deformation anisotropy due to the formation of a specific texture feature. In this study, the texture feature of pure titanium foil with different cold‐rolling reduction is characterized by electron back‐scattered diffraction (EBSD), and the effect of cold‐rolling deformation on texture evolution and tensile properties of titanium hfoil are systematically investigated. The results show that the cold‐rolling reduction could significantly affect the tensile anisotropy of titanium foil by regulating the texture characteristics. At the low level of cold‐rolling reductions (0%–30%), the texture of titanium foil is mainly pyramid texture, causing the obvious tensile anisotropy. At the medium level of cold‐rolling reductions (50%), strong basal‐plane texture components are appeared, causing that the activated slip system along transverse direction (TD) or normal direction (ND) is almost the same, and thus the tensile anisotropy gradually diminishes. At the high level of cold‐rolling reductions (70%), the intensity of basal‐plane texture becomes weak, and the tensile anisotropy appears in titanium foil again. The findings could provide theoretical guidance and technical support for the preparation of weak anisotropic titanium foil for hydrogen fuel cell. [ABSTRACT FROM AUTHOR]

To control the precipitation sites of carbides, the cold rolling, annealing, and aging processes were employed to process Fe-26Mn-10.2Al-0.98C-0.15 V (wt.%) steels with duplex structure. After aging, the alloy achieved a good combination of strength and plasticity, which had a yield strength of 1120 MPa, tensile strength of 1285 MPa, and elongation of 17%. The precipitation strengthening of the κ-carbides shows a significant contribution to the high yield strength of this alloy. The strengthening models were employed to calculate the precipitation strengthening from coherent κ-carbides, and show good prediction performance. The increase in strength slows down with increasing aging time, which is influenced by the critical grain size of the precipitated particles and the antiphase boundary energy ( γ APB ). Furthermore, the deformation mechanism of this alloy is influenced by the high SFE and the softening effect of the intragranular κ-carbide sliding surface. The analyses of the deformed structure revealed that the plastic deformation was dominated by the planar slip, resulting in the formation of the Taylor lattice, a special dislocation substructure. [ABSTRACT FROM AUTHOR]

The effect of modes of deformation (unidirectional, two-step and multi-step-cross rolling) by cold rolling on microstructure, texture, and mechanical properties of the Ni-16Cr and Ni-16Mo alloys has been discussed in this work. The overall texture intensities of both the alloys are always strong in unidirectional mode of cold rolling after 90% deformation as compared to two-step and multi-step cross rolling. There is a strong bearing between the overall texture intensity and intensity of the Brass ({0 1 1}〈2 1 1) component of 90% deformed sheets irrespective of the modes of deformation and alloy system. The evolution of {111}-fibers is an important phenomenon during cold rolling of both the alloys which appear to be stable in a particular range of overall intensity of ODF (Orientation Distribution Function) and this range varies with modes and extent of deformation. The alloy Ni-16Mo exhibits better mechanical properties than the alloy Ni-16Cr in 90% deformed condition. The measured values of relative resolved shear stress corresponding to the strongest texture present in the 90% deformed sheets well explain the variation in uniform elongation with change in modes of deformation. Both the alloys in highly (90%) deformed condition display two-slope behavior and follow Ludwigson (with negative deviation at low strain) and Voce relationships. The instantaneous work hardening curves of both the alloys show continuous decrease of work hardening till it attains saturation in the last stage of plastic deformation before necking. The linear portion of this last stage has been explained using Kock-Mecking-Estrin analysis and correlated with overall uniform elongation. [ABSTRACT FROM AUTHOR]

Two nominal Fe35Ni35Cr20Mn10 (in at.%) multi-principal-component alloys (MCAs) were prepared in vacuum-induction furnace with industrial purity (IP, > 98.5wt.%) and high-purity (HP, > 99.5wt.%) raw metals, respectively. The microstructure was characterized by XRD, SEM and TEM. Tensile mechanical properties and continual plastic deformation ability of them after hot-forging + homogenization annealing were examined by tensile test and continuous cold rolling test. For IP-MCA, the content of "impurity" elements (other elements excluding Fe, Ni, Cr and Mn) is high to 1.68wt.%. However, only single-FCC phase is detected by XRD and no any second phase particles are observed by SEM and TEM, just like that in HP-MCA with an impurity content of 0.4wt.%. It is interesting to find that IP-MCA possesses the equally excellent strength and elongation like HP-MCA. Cold rolling examination indicates that the sheet of IP-MCA with a thickness of 14.0 mm can be continuously rolled to a thin-strip of 0.35 mm. This exhibits an extremely excellent continuous plastic deformation ability, like HP-MAC. Thus, due to much lower cost, IP-MCA can be reliably step toward manufacturing industrial productions. Due to the tortile lattice in physic process for a give MCA system, the tolerability to impurity elements is thought to be large. [ABSTRACT FROM AUTHOR]

The metal manufacturing industry employs the reversible cold rolling mill, which is a machine used to process and shape various metal products such as steel sheets, aluminum sheets, and copper sheets. High accuracy control of web velocity and web tension is essential in the manufacturing process for preventing the web from bending or breaking during the entire manufacturing process. In this work, we introduce a control law design method using PI control with unknown parameters for the web winding system to ensure that the final product will not be affected by deformation or breakage. In the first step of the adaptive backstepping procedure, the integral action is obtained by adding the integral of the tracking error to the error considered. The stability of the control design is ensured by the Lyapunov stability theorem. It verifies that the trajectory dynamics are asymptotically stable. To illustrate the effectiveness and performance of the proposed controllers, simulation studies using the MATLAB/Simulink environment are presented. [ABSTRACT FROM AUTHOR]

316L austenitic stainless steel (ASS) with a heterogeneous structure exhibits favorable mechanical properties at room temperature, promising excellent application potential. However, the thermal stability of 316L ASS with heterogeneous lamella structure (HLS) has not been adequately addressed yet. Herein, an HLS of 316L ASS is fabricated through 78% cold rolling followed by annealing at 750 °C for 13 min. The detailed investigation focuses on the influence of microstructure evolution on the mechanical properties and corrosion resistance of the alloy after aging at temperatures ranging from 350 to 550 °C for 100 h. The results show that a notable quantity of residual martensite persists even after annealing at high temperatures for a brief duration. The dislocation density of the test steel is reduced after long‐term aging treatment, and the residual martensite is further reversed into austenite during aging. In addition, the aging treatment also promotes further growth of nanocrystalline/ultrafine‐grained, which weakens the heterogeneous characteristics of HLS 316L ASS, resulting in a slight decrease in mechanical properties. However, the decrease in defect density and the enhancement of recrystallization degree are beneficial for eliminating most of the corrosion‐sensitive areas in the cold‐deformed structure, thereby improving the corrosion resistance. [ABSTRACT FROM AUTHOR]

Based upon calculated data compositions of experimental aluminum alloys, which are characterized by the lowest tendency towards hot brittleness during casting, are selected. Sheets 2.5 mm thick are obtained from ingots of experimental alloys by hot rolling. It is shown that weldability of the Al–1Ca–5.5Zn–1.5Mg–0.5Mn alloy is at the level of that for serial alloy 1915. Analysis of the obtained data shows that cracking characteristics of the Al–2Ca–2.5Mg–0.4Mn alloy (alloy 2) (specimen cracking coefficient and critical deformation rate) are at a level corresponding to AMg3 alloy. The alloys studied with appropriate surface preparation are not prone to pore formation during fusion welding. Mechanical properties of joints of the alloys studied during argon-arc and plasma welding are determined. [ABSTRACT FROM AUTHOR]

The microstructure and texture evolution of Cu-Ni-P alloy after cold rolling and annealing at 500 °C was studied by electron backscattering diffraction (EBSD). The equiaxed grain is elongated and the dislocation density increases gradually after cold rolling. The grain boundaries become blurred and the structure becomes banded when the reduction in cold rolling reaches 95%. A typical rolling texture is formed with the increase in deformation amount in cold rolling. The deformation structure gradually disappeared and recrystallized new grains were formed after annealing at 500 °C. The recrystallization nucleation mechanism of Cu-Ni-P alloy at 60% reduction is mainly a bow nucleation mechanism. A shear band begins to form after annealing at 80% reduction. The shear band becomes the preferred nucleation location with the increase in reduction. Most adjacent recrystallized grains growing in the shear band have a twin relationship. [ABSTRACT FROM AUTHOR]

The thermal properties, microstructure, and mechanical properties of Fe-18Mn-3Ti (wt%) were investigated, focusing on the effects of different heat-treatment processes. Results revealed that the 450 °C warm-rolling sample (450 WR) exhibited promising mechanical properties. Specifically, this sample displayed a yield strength of 988 MPa, an ultimate tensile strength of 1052 MPa, and total elongation of 15.49%. Consequently, a favorable strength-ductility balance was achieved. The strain-hardening ability surpassed that of the cold rolling sample (CR). Microstructure analysis indicated the simultaneous occurrence of dynamic equilibrium between grain deformation and re-crystallization because of the co-influence of thermal and strain in the warm rolling process. This desirable mechanical property was attributed to the presence of a multi-phase (α-martensite, austenite, and ε-martensite) and heterogeneous microstructure. The improvement of ultimate tensile strength was based on grain refinement, grain co-deformation, and the transformation-induced plasticity (TRIP) effect in the early stage of plastic deformation (stage Ⅰ). The improvement of ultimate elongation (TEL) was ascribed to the TRIP effect in the middle stage of plastic deformation (stage Ⅱ). [ABSTRACT FROM AUTHOR]

This study focuses on the heavily Mg-doped GaN in which the passivation effect of hydrogen and the compensation effect of nitrogen vacancies (VN) impede its further development. To investigate those two factors, H ion implantation followed by thermal annealing was performed on the material. The evolution of relevant defects (H and VN) was revealed, and their distinct behaviors during thermal annealing were compared between different atmospheres (N2/NH3). The concentration of H and its associated yellow luminescence (YL) band intensity decrease as the thermal annealing temperature rises, regardless of the atmosphere being N2 or NH3. However, during thermal annealing in NH3, the decrease in H concentration is notably faster compared to N2. Furthermore, a distinct trend is observed in the behavior of the blue luminescence (BL) band under N2 and NH3. Through a comprehensive analysis of surface properties, we deduce that the decomposition of NH3 during thermal annealing not only promotes the out-diffusion of H ions from the material, but also facilitates the repair of VN on the surface of heavily Mg-doped GaN. This research could provide crucial insights into the post-growth process of heavily Mg-doped GaN. [ABSTRACT FROM AUTHOR]

Phase transformations in cold-rolled (CR) 304L austenitic stainless steel were studied using different techniques, including dilatometry, X-ray diffraction and scanning electron microscopy. During continuous annealing, the dilatometric measurements indicated that the evolution of the deformed microstructures led to an important anomaly constituted of two contractions. Quantitative processing of the X-ray diffraction results allowed the determination of the temperature-dependence of α′-martensite and austenite (γ), phase fractions, dislocations density and lattice strains on heating to 900°C. It is demonstrated that the first contraction is due to the recovery of α′- and γ-phases. In this temperature range, it is suggested that the recovery in CR γ has caused the growth of surrounding α′ particles which competes with the reversion of the smallest α′ particles. The second contraction, on the other hand, has been attributed to the α′ reversion and recrystallization in CR γ regions. [ABSTRACT FROM AUTHOR]

LZ91 Mg-Li alloy plates with three types of initial texture were rolled by 70% reduction at both room temperature and 200 °C to explore the rolling texture formation of α-Mg phase. The results showed that the rolling texture is largely affected by the initial texture. All the samples exhibited two main texture components as RD-split double peaks texture and TD-split double peaks texture after large strain rolling. The intensity of the two texture components was strongly influenced by the initial orientation and rolling temperature. Extension twinning altered the large-split non-basal orientation to a near basal one at low rolling strain. The basal orientation induced by twinning is unstable, which finally transmitted to the RD-split texture. The strong TD-split texture formed due to slip-induced orientation transition from its initial orientation. The competition between prismatic 〈 a 〉 and basal slip determined the intensity and tilt angle of the TD-split texture. By increasing the rolling temperature, the TD-split texture component was enhanced in all three samples. Limitation of extension twinning behavior and the promotion of prismatic slip at elevated temperature are the main reasons for the difference in hot and cold rolling texture. [ABSTRACT FROM AUTHOR]

Incoloy 800 is a Fe-based super alloy used primarily in high-temperature applications like boilerplates due to its ability to maintain its austenitic phase. Samples of 100 × 20 × 5 mm were manufactured in vertical orientation using selective laser melting (SLM) and were annealed at 980 °C for 15 min. Annealed samples were cold rolled at room temperature, in multiple passes to 20, 40, 60 and 80% reduction in thickness, perpendicular to the building direction. The aim of this study is to understand the strain hardening effect upon rolling and also to know the effect of cold rolling on texture, microstructure and hardness after rolling the annealed alloy. Microstructural features were observed under optical microscope and scanning electron microscope while the texture measurement was done using X-ray goniometer. Typical fish scale morphology was observed in the transverse plane of as-built condition, which was diminished in annealed samples. SEM study shows fine grains along with traces of lamellar cell morphology. Hardness increased with an increase in percentage reduction. Austenite (γ) phase was detected as the only phase in XRD analysis. The bulk texture of annealed sample revealed strong copper texture until 40% rolling, and thereafter, it reduced. Goss texture component showed a similar trend, while brass texture increased up to 60% rolling condition and thereafter diminished. [ABSTRACT FROM AUTHOR]

In this study, an excellent correlation has been established between the microstructure, texture, and mechanical properties of cold-rolled Ni-16Cr, Ni-16Mo, and Ni-16Cr-16Mo alloys after subjecting them to a similar level of deformation that is 30, 50, and 90 percent cold-rolling reductions. A significantly higher (>50 pct.) twin fractions parallel to RD in alloys Ni-16Cr (after 30 and 50 percent rolling reductions) and Ni-16Cr-16Mo (after 50 percent rolling reduction) assist in the development of {111}-fiber which significantly affects the overall texture of the materials. The alloy Ni-16Mo, which does not form {111}-fiber in the complete range (30, 50, and 90 percent) of rolling reductions, displays an overall higher texture than the other two alloys Ni-16Cr and Ni-16Cr-16Mo. At lower rolling reduction (30 percent), the β-fiber skeleton line of alloy Ni-16Cr-16Mo resembles with alloy Ni-16Mo, while at higher rolling reductions (50 and 90 percent), the β-fiber skeleton line of alloy Ni-16Cr-16Mo matches with the alloy Ni-16Cr. The alloys containing element Mo such as alloys Ni-16Mo and Ni-16Cr-16Mo display higher tensile strength and ductility after 90 percent rolling reduction as compared to alloy Ni-16Cr. The overall anisotropy is highest, intermediate, and lowest for alloy Ni-16Cr, Ni-16Mo, and Ni-16Cr-16Mo, respectively, at any particular rolling reduction and are best explained by the theory of relative resolved shear stresses of important slip systems in the presence of important texture component present in the corresponding alloys. [ABSTRACT FROM AUTHOR]

Incoloy 800 is an iron-based Ni-Cr super-austenitic stainless steel that finds applications involving exposure to high temperatures and corrosive environments. This study aims to investigate the effect of cold rolling on the microstructure, texture and hardness of Incoloy 800 fabricated by selective laser melting. Rectangular specimens of 100 × 20 × 5 mm were printed in the vertical build orientation. The as-built alloy was subjected to unidirectional cold rolling along the long transverse plane to achieve thickness reductions of 20, 40, 60 and 80%. Optical and scanning electron microscopy were used to observe the microstructure. EDS was used to find the elemental composition. An x-ray goniometer was used to measure the bulk texture. Vickers hardness test was performed to measure the hardness. The optical micrographs of the as-built sample revealed a laser scan track pattern on the top surface, whereas the short and long transverse sections revealed typical fish-scale morphology with overlapping melt pool boundaries. Melt pool widening was observed upon increasing the rolling percentage. Scanning electron microscope revealed three types of grain morphology–cellular, elongated cellular and columnar. X-ray diffraction revealed the presence of austenite (γ) phase. The as-built alloy showed cube, goss and copper texture components. The sample rolled to 80% reduction showed strong brass and a weakened goss component. The 80% cold-rolled sample showed 42 and 116% higher hardness than the as-built condition and as-cast condition, respectively, due to strain hardening. [ABSTRACT FROM AUTHOR]

The production of medium-alloyed (with Si content < 2.80% and Al content < 1.0%) cold-rolled high-permeability electrical isotropic steels (EIS), supplied using the full-process technology and in a semifinished state (semiprocess technology) is considered. The effect of tin content in the metal exerted on the texture and magnetic properties of EIS after the final recrystallization annealing of cold-rolled steel is established. Combined alloying of steel with aluminum (Al < 1.0%), tin (Sn > 0.02%) or antimony (Sb > 0.02%) makes it possible to improve the texture of finished and semifinished EIS and, as a result, to provide a significant decrease in the level of specific magnetic losses. The effect of the microstructural parameters inherent in annealed cold-rolled metal exerted on the magnetic induction and magnetic permeability of finished and semifinished EIS has been studied. The effect of cold-rolling modes and heat treatment of cold-rolled steel on the formation of the microrelief of the strip surface and the mechanical properties of semifinished EIS is considered. [ABSTRACT FROM AUTHOR]

The method is aimed at comparing the lubricating capacity of different emulsions. The purpose of the work is to evaluate the possibility of using a universal friction machine, type MMW-1A, to determine the value of the friction coefficient in the cold rolling of very thin strips of carbon steel. The article analyzes the research related to the methods of measuring the friction coefficient in lengthwise rolling. The methodology of experiment determination of friction coefficient value between the material of RCM-1250 reversing mill rolls (steel of working rolls—analog of 60S2HFA steel) and the sample of annealed strip, 0.224-mm thick, made of TS-435 steel grade (analog of 08ps steel, GOST 1050) has been developed. The selected friction conditions are semi-fluid friction. The experiment applied the emulsion, based on the lubricating-cooling liquid, such as Quaker 2185, and used an RCM-125 reversing mill. Two types of ring-shaped samples made of roll material were used in the experiment with wall thicknesses of S = 4 mm and S = 2 mm. The results of the experiments showed that the use of the ring-shaped sample with S = 4 mm is more reasonable from the point of view of stability of the created friction conditions. The recommended average value of friction coefficient between the above materials of rolls and strip was determined: fcf = 0.038. In the course of the experiment the values of the friction coefficient fluctuated within the boundaries, from the minimum of fmin = 0.012, to the maximum of fmax = 0.048. In general, these experimental results are correlated with reference data on the value of the friction coefficient for this type of rolling and the results of other experiments described in the literature, conducted under similar friction conditions. Proceeding from this, it is possible to draw a conclusion that estimation of the lubricating capacity of various lubricating-cooling liquids, application of universal friction machines of the design described in the article is expedient. [ABSTRACT FROM AUTHOR]

As a promising new material, silver thin film has been widely used in modern industry. Magnetron sputtering with a silver target as the source has become a common method to produce silver film. In this research, the sputtering performance of Ag targets in cold rolling state and annealing state was compared and the relationship between the Ag targets and Ag thin films was explored. The results show that annealing at 600 °C after cold rolling to a deformation of 83.33% can effectively increase the texture density of {110} in Ag. Both in the cold rolling state and annealing state, Ag targets exhibited a similar deposition rate. The resistivity of both kinds of Ag thin films decreases with the sputtering time. Ag thin films formed by sputtering Ag targets of two states for the same sputtering time displayed different resistivity, with the annealing state being superior over the rolling state. Ag target in annealing state, owing its uniform microstructure, showed shallower depth of rack track after sputtering. Annealing treatment after cold rolling is an alternative method to improve the target microstructure. [ABSTRACT FROM AUTHOR]

In the present study, microstructure and cyclic tensile tests were used to measure the superelastic responses of Fe40.95Ni28Co17Al11.5Ta2.5B0.05 (at.%) shape memory alloys after 97% cold rolling. Cold-rolled samples underwent annealing heat treatment (1250 °C/1 h) followed by quenching in water or aging heat treatment (700 °C/6 h and 700 °C/12 h) followed by quenching in water. The microstructure results showed that the average grain size increased from 210 μm to 1570 μm as annealing times increased from 0.5 h to 1 h. X-ray diffraction (XRD) spectra for FeNiCoAlTaB (NCATB) showed that in cold-rolled alloys after solution, the strong peak was in the face-centered cubic (γ, FCC) <111> structure. In aged samples, a new peak (γ', FCC) emerged, the intensity of which increased as aging times rose from 6 to 12 h. Transmission electron microscope (TEM) images showed that the average precipitate size was around 10 nm in 700 °C/6 h specimens and 18 nm in 700 °C/12 h specimens. The precipitate was enriched in Ni, Al, and Ta elements and exhibited an L12 crystal structure. Tensile samples aged at 700 °C for 6 and 12 h exhibited recoverable strains of 1% and 2.6%, respectively, at room temperature. Digital image correlation (DIC) results for the sample aged at 700 °C for 12 h showed that two martensite variants were activated during the superelastic test. Such variants can form corresponding variant pairs (CVPs), which promote tensile deformation. The tensile sample exhibited a gradual cyclic degradation, and a large irrecoverable strain was observed after the test. This irrecoverable strain was the result of residual martensite, which was pinned by dislocations. [ABSTRACT FROM AUTHOR]

Production of high-Mg content Al–Mg alloys in the form of sheet from cast condition, should be performed with some pre- and post-deforming treatments to achieve desirable mechanical properties. In this research, to find the necessity and influence of pre- and post-rolling homogenisation process on Al–6Mg alloy properties, series of experimental investigations were carried out on direct chill (DC) cast Al–6Mg. Hot extrusion at the temperature of 350°C has been selected as a pre-rolling homogenisation process, which leads to homogenisation by formation of partially recrystallised grains. Cold rolling performed on both DC cast and hot extruded samples up to 80%. Post-rolling homogenisation process done by annealing at 350, 450 and 550°C. Results show that pre-rolling hot extrusion is effective for stability of mechanical properties after cold rolling. Good combination of strength and ductility is achieved for the cold-rolled sample followed by annealing at 450°C. Changes in strength and ductility of the alloy after both pre- and post-rolling homogenisations are controlled by recovery resulting from dislocation arrangement and formation of subgrains. Both pre- and post-rolling homogenisation are effective in improving mechanical properties of cast Al–6Mg, however post-rolling process is more effective if the annealing temperature is chosen correctly. [ABSTRACT FROM AUTHOR]

It has been tried in this research for investigating the microstructure and texture of Al0.3CoCrFeNi after the cold rolling process. At first, an ingot was made by vacuum arc melting. Then, homogenization heat treatment was done at 1050 °C for 10 h to eliminate casting defects. After that, cold rolling deformation with 75% reduction was applied, and the thickness of the ingot reached 2 mm from 8 mm. Finally, annealing heat treatment at 1050 °C for 1h was done to remove work-hardening effects after cold deformation. Also, for the investigation of microstructure and texture, optical and scanning electron microscopy was used, and also for studying macro-texture, X-ray diffraction method was used. Investigation of pole figures and orientation distribution function shows that grains have preferred orientation in the rolling direction after cold rolling deformation. In contrast, grains have random orientation in the homogenized and annealed specimens. Also, the copper component was dominated after cold rolling, while the cubic component was dominated in the homogenized specimen. Furthermore, copper component led to low ductility and improved the mechanical properties of alloy. Also, after annealing heat treatment, the copper component was removed, and the intensity of other components was decreased except the cubic component and formation of cubic component after annealing heat treatment in this alloy led to improving the ductility and decreasing mechanical properties. [ABSTRACT FROM AUTHOR]

A dual-heterogeneous structure with both heterogeneous grain structure and coherent L12 nano-precipitate was obtained in a (FeCoNi)86Al7Ti7 medium-entropy alloy (MEA) after cold rolling, critical annealing, and aging treatments. The volume fraction of the L12 phase is found to increase from 0% to 34.5% after aging treatment, resulting in severer heterogeneity. The unaged samples of (FeCoNi)86Al7Ti7 MEA are found to have a much better synergy of strength and ductility as compared to the FeCoNi MEA. Moreover, the tensile properties for the aged samples of (FeCoNi)86Al7Ti7 MEA with dual-heterogeneous structures are even better than those for the corresponding unaged samples. The hetero-deformation-induced hardening plays a more important role in the aged samples than in the unaged samples, producing a higher density of geometrically necessary dislocations. High density dislocations are discovered in grain interiors for the aged samples and the deformation is dominated by the planar slip in the unaged samples. Meanwhile, a high density of dislocations are observed inside L12 nano-precipitates; thus, L12 nano-precipitates can be sheared by dislocations, indicating that L12 nano-precipitates are strong but deformable. The strong interactions between dislocations and L12 nano-precipitates should provide additional strain hardening for better tensile properties in the aged samples. [ABSTRACT FROM AUTHOR]

Production of a thin cold rolled sheet of high silicon electrical steel is industrially challenging as it is associated with the formation of different types of cracks. The present study investigates the role of microstructure, crystallographic texture, and analytical stress state on the formation of alligator crack and edge crack during cold rolling of Fe-3.78 wt. % Si electrical steel. Owing to high strain incompatibility, alligator crack initiates from shear bands, which develops during cold rolling. Furthermore, the large difference in Taylor factors of {111}⟨110⟩ and {001}⟨110⟩ oriented grains assisted the crack to follow the hot band interface. Stress analysis based on the finite element method indicates that minor tensile stress in the normal direction develops during the exit stage of cold rolling. This tensile stress has been found to be sufficient to cause cleavage fracture during the last step of alligatoring. The crack propagation is assisted by the large size and favorable orientation of θ-fiber (ND||⟨001⟩) textured grains. On the other hand, the finite element method-based analysis suggests that high tensile stress at the edges during steady state condition initiates the cleavage edge crack, which propagates inward along the transverse direction during the final exit stage. Intermediate annealing and hot band annealing were found to be effective in eliminating the formation of alligator crack and edge crack, respectively. [ABSTRACT FROM AUTHOR]

A new method to prepare large Cu–Cr alloy with both high strength and high conductivity has been developed. Cu–Cr billets are produced efficiently by laser additive manufacturing, and the microstructure of the alloy is changed by severe plastic deformation caused by large cold rolling ratio. The strength of the alloy can be significantly increased to 677 MPa by eliminating pores, introducing texture and refining grain. The deformation twins caused by plastic deformation processing make up for the plasticity loss caused by grain refinement. With the increase of density and the deformation of Cr particles, the electrical conductivity of the alloy is increased to 28.7 MS/m. Our findings not only deepen the understanding of laser additive manufacturing of highly reflective metals, but also provide a new idea for the preparation of high-strength and high-conductivity Cu alloy workpieces.

This study presents processing and properties of dual-phase (DP) steels, which contain islands of martensite among ferrite grains effectively reinforced by abundant carbide particles. To this end, a medium-carbon, low-alloyed steel plate with an initial ferrite-pearlite microstructure underwent cold rolling for 80% thickness reduction. Specimens obtained from the cold rolled strip were then heated in a neutralized salt bath at various temperatures ranging from 600 to 730 °C for 10 ks, followed by water quenching. The resulting microstructures and mechanical properties were analyzed. Preceding the formation of austenite during intercritical annealing, recrystallization led to the formation of a spheroidized ferrite microstructure with a high number of carbide particles dispersed mainly within the recrystallized ferrite grains. Initially, austenite grains formed on the carbides located at the boundaries between ferrite grains, followed by the formation of austenite on the carbides still present within the ferrite grains. Quenching from 715 °C resulted in a DP microstructure with intergranular martensite while increasing the annealing temperature to 725 °C led to the creation of intragranular martensite additionally. The study also focused on the distribution of alloying elements in the DP microstructure, revealing an enrichment of carbides with Mn, Cr, and Mo. Furthermore, an enrichment of martensite islands with manganese atoms was identified, but no comparable enrichment with carbon atoms was observed. The specimens annealed at 715–725 °C, which consisted of a martensite volume fraction ranging from 0.15 to 0.45, exhibited a superior balance of strength and ductility, as well as an outstanding work hardening exponent.

The paper presents an analysis of the methodology for calculating the parameters of hot‑rolled low‑carbon steel strip on a 1600 wide strip mill. Based on the analysis, a computer program for quick calculation of rolling parameters has been developed. A solid‑state model was constructed and the rolling process was simulated in the QForm environment. A comparative analysis was carried out with the passport data of the “Danieli” unit based on the modeling results. The obtained modeling results do not exceed the maximum allowable deviations for rolling force and geometric parameters of the hot‑rolled strip.

Explosion protection is of particular importance for safety as explosions also endanger the health of workers due to the uncontrolled effects of flames and pressure, the presence of harmful reaction products and the consumption of oxygen in the ambient air breathed by workers. CuAlBe alloy is proposed as a solution for mechanical actuators such as gears that work in environments with possible explosive atmosphere. Made of CuBe master alloy and pure aluminum in a induction furnace the material present large grains in melted state. After the hot rolling (heated 600s at 900°C) of the ingots small variation of chemical composition was observed based on the oxidation of the material, appearance of small cracks on the edges and a preferential orientation of the grains along the lamination direction. Scanning electron microscopy (SEM) was used to characterize the microstructural states of CuAlBe as laminated and heat treated states.

In order to reduce the deformation resistance, the rolling process of metastable β titanium alloys is generally carried out in the β single-phase state, which causes the problem of non-uniform grain size during the subsequent annealing process, thus affecting the alloy properties. Here we first solution-treated the as-cast Ti–15Mo–3Al-2.7Nb-0.2Si alloy at 740 °C to obtain α + β phase, then cold rolled it with a reduction of 60 %, and finally annealed it at 710–810 °C for 2–240min. Characterization of the annealed metastable β alloy revealed that α phase was involved in the rolling deformation at the same time and recrystallized on the β matrix during the subsequent annealing process, known as equiaxial dispersion, which impeded the recrystallization of the β grains, and ultimately an ultrafine crystalline microstructure of α + β phases with an average grain size of less than 2 μm was obtained.

In this research, the effects of thermomechanical treatment including heavy cold rolling and post-deformation annealing on the improvement of shape recovery in an Fe–9Ni–7Mn (at.%) martensitic alloy were investigated. Experimental results showed that the 80 % cold rolling produced a little fraction of strain-induced austenite phase in the martensitic matrix due to the strain concentration in the microstructure and the temperature rise under deformation. During post-deformation annealing at 590 °C in a dual phase (α+γ) region, a greater fraction of the austenite was introduced in the martensitic matrix such that its amount first increased by increasing the annealing time to 1.8 ks and then decreased at a more time of reversion. The microstructural evolution revealed that the austenite reversion under post-deformation annealing initially occurred by a shear nature at the early steps of reversion and then continued by diffusion. Tensile testing represented a good mixture of a relatively high ultimate tensile strength of ∼780 MPa and proper ductility of ∼8.5 % in the post-deformation annealed (PDA) sample for 0.9 ks. In addition, the shape memory properties were examined under the conditions of cold rolling and post-deformation annealing. The results showed a maximum shape recovery rate of ∼23 % for the cold rolled specimen which increased to ∼50 % after post-deformation annealing for 0.9 ks. The presence of a relatively high amount of retained austenite with proper stability and strength in the microstructure of the PDA sample for 0.9 ks was the reason for achieving the highest value of shape recovery.

An accurate and numerically efficient description of the rolling process is a challenging task since the degree of computational accuracy is directly related to the complexity of the algorithm employed. In the most general case, finite element models (FEM) are used for the simulation of deformation processes; however, these techniques require significant computational time. Analytical approaches, which are suited for one or another deformation process, seem to be a proper alternative to FEM. In this study, the well-established flowline modeling approach (FLM) is extended with the aim of better describing the flow of a rolled material in both surface and subsurface regions. A new flowline function is defined, while the velocity along the particular streamline and strain rate gradients are determined analytically, based on the roll gap geometry. The new model is validated by comparing the velocity components to the ones computed by the finite element model. The distortion of meshes predicted by both FEM and FLM follow the same evolutionary pattern.

Industries operating in extreme conditions demand materials with exceptional strength, fatigue resistance, corrosion resistance, and formability. While AA5052 alloy is widely used in such industries due to its high fatigue strength and corrosion resistance, its strength frequently falls short of stringent standards. For AA5052 alloy, this study explores the combined use of solutionizing and cryo-rolling, followed by annealing, to improve strength. Although several alloys have been reported to undergo solution treatment before cryo-rolling, this study focuses on how post-processing via annealing can lessen the formability constraints usually connected to conventional cryo-rolling. The study sheds light on the ways that solutionizing, cryo-rolling, and annealing interact to affect the alloy’s mechanical characteristics. Microstructure analysis shows that solutionizing improves the grain structure by reducing dynamic recovery, promoting dislocation density, and facilitating precipitate formation. Sheets subjected to solutionizing + cryo-rolling and partially annealed at 250 °C produce optimal results. Interestingly, formability is decreased when cryo-rolling alone is used instead of cold rolling, whereas formability is successfully increased when solutionizing is used. Comparing solutionized + cryo-rolled sheets that are partially annealed at 250 °C to cold-rolled sheets that are annealed at the same temperature, the former show notable quantitative improvements: a notable 17% increase in ultimate strength, a 10% boost in yield strength, and a noteworthy 13% enhancement in microhardness. Formability has improved with the solutionized + cryo-rolled specimens by annealing. This proposed approach led to noticeable gains in formability, hardness, and strength, which would significantly improve material performance for industrial applications.

The shape of laminated products is a crucial parameter in high-speed and high-volume finishing lines where they must fulfill tight tolerances. Latent defects are detected by flatness rolls (or shapemeter rolls) inserted in the manufacturing line for online flatness control. A prototype of flatness roll has been developed with high spatial resolution (5 mm) and measurement capability over a thickness range of 0.1–1 mm to evaluate flatness and residual stresses of flat metal strip products manufactured by continuous cold rolling (ultra-thin sheets for packaging and automotive markets). The flatness roll prototype relies on pressure-induced strain sensing on segmented blades using Fiber Bragg Grating technology. Synchronous measurement of the flatness profile across strip width rejects disturbances of strip tension during rolling. We provide a proof-of-concept on pilot lines in both static and dynamic conditions (e.g., roll in rotation and in contact with a strip under tension) and the sensing mechanism shows a capability above 3. This combination of performances remains unique up to now. Interblade crosstalk appears to be an important issue. We propose a crosstalk model that agrees with experimental coupling coefficients. A crosstalk matrix inversion yields the distribution in contact pressure from strain data measured on the reverse side. Additional work will be required to use the flatness roll in industrial conditions. [ABSTRACT FROM AUTHOR]