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Aluminum and its alloys are widely used in the busbar structures of electrolytic aluminum production. However, they are prone to corrosion and wear damage during use, leading to a decline in current-transmission efficiency and potentially causing safety issues. To repair damaged aluminum busbars, this paper explores the feasibility of using cold spraying technology for surface restoration. Using 6063 aluminum alloy as the substrate, AlZn/nickel-plated graphite composite coatings were applied through cold spraying. The effects of different nickel-plated graphite contents on the microstructure, mechanical properties, and corrosion resistance of the coatings were studied. Annealing treatments (200 °C, 300 °C, 400 °C) were further used to improve the coating's density and performance. The results show that with an increase in the nickel-plated graphite content, the porosity of the coating gradually increases, while the coating's density and bond strength improve. Additionally, the annealing treatment significantly enhanced the uniformity and hardness of the coating. Moreover, the cold-sprayed coatings exhibited excellent corrosion resistance, especially in the annealed coatings, which showed superior microstructural stability and lower corrosion current density. This study provides a new technological approach for the repair of aluminum busbars and offers an in-depth discussion on the application of cold spraying technology in the surface restoration of aluminum-based composite materials. [ABSTRACT FROM AUTHOR]

This study has investigated the effects of different annealing temperatures on the microstructure, chemical composition, phase structure, and piezoelectric properties of ZnO films. The analysis focuses on how annealing temperature influences the oxygen content and the preferred c-axis (002) orientation of the films. It was found that annealing significantly increases the grain size and optimizes the columnar crystal structure, though excessive high-temperature annealing leads to structural degradation. This behavior is likely related to changes in oxygen content at different annealing temperatures. High resolution transmission electron microscopy (HR-TEM) reveals that the films exhibit high-resolution lattice stripes, confirming their high crystallinity. Although the films exhibit growth in multiple orientations, the c-axis (002) orientation remains the predominant crystallographic growth. Further piezoelectric property analysis demonstrates that the ZnO films annealed at 400 °C exhibit enhanced piezoelectric performance and stable linear piezoelectric behavior. These findings offer valuable support for optimizing the piezoelectric properties of ZnO films and their applications in piezoelectric sensors. [ABSTRACT FROM AUTHOR]

In recent years, the fabrication of materials with large nonlinear optical coefficients and the investigation of methods to enhance nonlinear optical performance have been in the spotlight. Herein, the bismuth telluride (Bi2Te3) thin films were prepared by radio-frequency magnetron sputtering and annealed in vacuum at various temperatures. The structural and optical properties were characterized and analyzed using X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, spectroscopic ellipsometry, and UV/VIS/NIR spectrophotometry. The third-order optical nonlinearities of Bi2Te3 thin films were investigated using the Z-scan technique, employing a 100 fs pulse width at an 800 nm wavelength. It is found that the crystallinity and the average grain size of the films increase with the annealing temperature. Meanwhile, the extinction coefficient of the annealed films increased, accompanied by a redshift in the optical bandgap. All samples exhibit pronounced saturable absorption and self-focusing behaviors. The nonlinear absorption coefficient and nonlinear refractive index of Bi2Te3 films annealed at 300 °C were found to be 2.44 times and 1.85 times higher than those of the as-deposited films, respectively. These findings demonstrate that annealing treatment is an effective approach to tuning the crystalline structure and linear optical properties of Bi2Te3 films while simultaneously enhancing their nonlinear optical performance. [ABSTRACT FROM AUTHOR]

This research endeavors to explore the potential of annealing treatment as a viable strategy to optimize the utilization of polypropylene (PP) composites, while preserving their exceptional properties. By incorporating ethylene vinyl acetate (EVA) copolymer and layered double hydroxide (LDH) into PP, this work meticulously analyzes the changes in crystallization behaviors and impact properties under varying annealing conditions. Impact strength is systematically assessed by a digital pendulum impact tester, whereas the crystalline structure is analyzed through polarized light optical microscopy (POM), differential scanning calorimetry (DSC), and x‐ray diffraction (XRD). The notch impact test exhibits a gradual increase in impact strength from 100 to 130°C, followed by a decline at 140°C. The XRD and DSC results elucidate subtle β‐crystal diffraction peaks for PP/EVA and PP/EVA/LDH composites, attributed to the transformative effect of EVA and LDH on PP crystals. POM analysis further unveils a reduction in spherical crystal size and gradual blurring of grain boundaries during the annealing process. Highlights: PP/EVA/LDH composites are effectively regulated by changing the annealing treatment conditions.The crystallization behaviors and crystal structure of PP are induced due to synergistic effect of EVA and LDH under annealing treatment.The toughness of PP is enhanced significantly by synergistic effect of EVA and LDH under annealing treatment. [ABSTRACT FROM AUTHOR]

An investigation was conducted to analyze the mechanical properties, wear behavior, and microstructure of coatings formed by high-velocity oxygen fuel spraying of CoMoCrSi powders. The effects of varying Cr concentration and particle sizes before and after heat treatment at 900 °C for 4 h were studied comparatively. The increase in Cr and Mo elements in the expanse of Co increased the structure's hardness before and after the heat treatment. As this increase was 10% in as-sprayed conditions, annealing raised the increase to 30%. Splat boundaries were the most vulnerable constituents against forces, creating a significant disadvantage in terms of structural integrity and affecting the overall performance. After annealing, the boundary strengths experienced a remarkable four-fold increase and cracks and fractures reduced significantly. The susceptibility of splat boundaries had a detrimental effect on room temperature wear behavior, and increased boundary densities led to a marked reduction in wear performance. Heat treatment induced improvements significantly increased the room temperature wear performance. At elevated temperature, the formation of oxide layers composed of CoMoO4, Co3O4, MoO3, and Cr2O3 overcame the weaknesses of the as-sprayed coating, reducing both the friction coefficient and wear losses. A reduced Co ratio led to the formation of an oxide blend with a higher concentration of Mo and Cr oxides on the surface, further improving the coating's wear behavior. [ABSTRACT FROM AUTHOR]

This study explores cobalt–cerium (Co90Ce10) thin films deposited on silicon (Si) (100) and glass substrates via direct current (DC) magnetron sputtering, with thicknesses from 10 nanometer (nm) to 50 nm. Post-deposition annealing treatments, conducted from 100 °C to 300 °C, resulted in significant changes in surface roughness, surface energy, and magnetic domain size, demonstrating the potential to tune magnetic properties via thermal processing. The films exhibited hydrophilic behavior, with thinner films showing a stronger substrate effect, crucial for surface engineering in device fabrication. Increased film thickness reduced transmittance due to photon signal inhibition and light scattering, important for optimizing optical devices. Furthermore, the reduction in sheet resistance and resistivity with increasing thickness and heat treatment highlights the significance of these parameters in optimizing the electrical properties for practical applications. [ABSTRACT FROM AUTHOR]

This study evaluates the mechanical and electrical properties of copper-clad aluminum (CCA) wire prepared with a total cross-section reduction of 89% through a multistage cold drawing process and subjected to annealing at various temperatures. In addition to the CCA wire, individual samples of oxygen-free copper and aluminum, drawn with a cross-sectional reduction of 50%, were annealed under the same temperature conditions to enable a comparative analysis. Tensile tests for strength and elongation measurements were conducted, while electrical conductivity was assessed through resistivity tests. SEM and EDS analyses were performed to examine the diffusion thickness and the composition of intermetallic compounds generated at the Al/Cu interface of CCA wire. The tensile strength of the CCA wire decreased and its elongation increased up to 250 °C, after which were maintained. As the annealing temperature increased, intermetallic compound layers of Al2Cu, AlCu, and Al4Cu9 were formed at the Al/Cu interface of the CCA wire, and their thickness increased. Electrical conductivity reaches a maximum at 200 °C and then continuously decreases, showing a negative linear correlation with an increase in the diffusion layer thickness of intermetallic compounds. The study confirmed that cold-drawn CCA wire achieves stable mechanical properties and maximum electrical conductivity at the optimal annealing temperature. [ABSTRACT FROM AUTHOR]

In order to enhance the resistance of superalloys to high-temperature molten chloride salt corrosion, Fe-Al coatings were prepared on 310S and 347H stainless-steel surfaces via pack aluminizing. Then, the coatings were annealed at different temperatures to explore the influence of temperature on their phase constitution, microstructure, microhardness, and corrosion resistance. The results showed that the annealing temperature had a considerable effect on the corrosion resistance of the Fe-Al coatings, which was related to the change in the phase composition of the coatings that occurred due to the annealing treatment. The growth rate of the coating on 347H steel was higher than that on 310S steel, and their thicknesses from aluminizing at 800 °C for 20 h were 209.6 and 153.5 µm, respectively. When annealing at 900 °C for 30 h, the phase composition of the coatings was completely transformed into (Fe, Cr, Ni) Al. The corrosion loss rate of the annealed coating was clearly reduced, the loss rate of the 310 coating was 6.0 and −0.25 mg/cm2 before and after annealing at 900 °C and that of the 347 coating was 4.89 and −0.7 mg/cm2 before and after annealing at 750 °C, respectively. The two coatings showed good corrosion resistance to molten chloride salts, as demonstrated by the oxide scale (Al2O3) that formed on the surface, which had a thickness of about 30~40 µm. [ABSTRACT FROM AUTHOR]

The present study examined the impact of single- and multi-stage austempering treatments on microstructural changes and the mechanical properties of AISI 4140 steel. All specimens underwent an annealing treatment before undergoing austempering treatments. The single-stage austempering treatment employed three distinct temperatures: 312, 362 and 412 °C. The multi-austempering employed three steps of austempering treatment, commencing at 312 °C and progressing in increments of 50 °C for an hour each, up to a maximum temperature of 412 °C. The mechanical properties were determined using hardness, impact and tensile testing. Furthermore, the microstructure alterations and phases identified in heat-treated specimens were characterised using scanning electron microscopy (SEM), electron dispersive spectroscopy (EDS) and X-ray diffraction (XRD) patterns. The mechanical properties of AISI 4140 steel subjected to single-stage and multi-stage austempering treatments exhibited a considerable enhancement compared to the annealed steel. The microstructure of annealed steel is predominantly coarse ferrite and pearlite. The austempering treatment forms a bainitic structure, retained austenite structures and a small number of martensitic structures within the steel's microstructure. In other words, the mechanical properties of AISI 4140 steel concerning austempering treatments are correlated with the microstructural changes resulting from different austempering temperatures.

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher 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.)

Aiming at the issues of small critical size and low glass forming ability of Fe-based amorphous alloys, this work focuses on solving the problem of preparing both large size and excellent properties. The highly dense FeCrMoBC bulk metallic glasses with diameter of 20 mm were prepared by spark plasma sintering, and the key role of heat treatment on the microstructure and properties of Fe-based bulk metallic glasses was investigated. The microstructure of Fe-based bulk metallic glasses was adjusted by annealing treatment, and the effects of annealing on the hardness and wear resistance of Fe-based bulk metallic glasses were studied. The results show that annealing induces partial crystallization of the alloy to construct in-situ amorphous nanocrystalline composites. After annealing at 650 °C for 1 h, Fe-based bulk metallic glasses precipitated Cr23C6 and B6Fe23 hard nanocrystalline phases. The highest Vickers hardness, highest fracture toughness, lowest friction coefficient, wear volume and wear rate were obtained, with values of 1514.68Hv, 2.81 MPa·m1/2,0.59, 4.72 × 10− 3mm3 and 2.62 × 10− 6mm3·N− 1·m− 1, respectively. Abrasive wear is the main form of wear, and the wear resistance is superior to that of GCr15. FeCrMoBC bulk metallic glasses exhibit outstanding hardness and wear resistance, providing new material options for the manufacture of high-performance advanced equipment. [ABSTRACT FROM AUTHOR]

The basal texture of traditional magnesium alloy AZ31 is easy to form and exhibits poor plasticity at room temperature. To address these problems, a multi-micro-alloyed high-plasticity Mg–1.8Zn–0.8Gd–0.1Ca–0.2Mn (wt%) alloy was developed using the unique role of rare earth and Ca solute atoms. In addition, the influence of the annealing process on the grain size, second phase, texture, and mechanical properties of the warm-rolled sheet at room temperature was analyzed with the goal of developing high-plasticity magnesium alloy sheets and obtaining optimal thermal-mechanical treatment parameters. The results show that the annealing temperature has a significant effect on the microstructure and properties due to the low alloying content: there are small amounts of larger-sized block and long string phases along the rolling direction (RD), as well as several spherical and rodlike particle phases inside the grains. With increasing annealing temperature, the grain size decreases and then increases, and the morphology, number, and size of the second phase also change correspondingly. The particle phase within the grains vanishes at 450°C, and the grain size increases sharply. In the full recrystallization stage at 300–350°C, the optimum strength-plasticity comprehensive mechanical properties are presented, with yield strengths of 182.1 and 176.9 MPa, tensile strengths of 271.1 and 275.8 MPa in the RD and transverse direction (TD), and elongation values of 27.4% and 32.3%, respectively. Moreover, there are still some larger-sized phases in the alloy that influence its mechanical properties, which offers room for improvement. [ABSTRACT FROM AUTHOR]

The research aims to investigate the generation and distribution of the residual stress in diamond thin films and explore methods of relieving it. Firstly, the finite element analysis software ANSYS Workbench was used to simulate the thermal stress of diamond thin films during the cooling process, and the effect of film thickness on thermal stress was studied. Then through the microwave plasma chemical vapor deposition (MPCVD), diamond thin films of varying thicknesses were deposited on aluminum nitride (AlN) ceramics substrates. The cooling duration was manipulated and annealing treatments were conducted. Characterization analyses were finally carried out using SEM and Raman spectroscopy. The simulation shows that after the cooling process, the distribution of thermal stress is irregular, with the maximum principal stress being tensile stress and the minimum principal stress being compressive stress. As the thickness of diamond thin films increases, the maximum principal stress shows an ascending trend, reaching a peak value of 373 MPa when the film thickness is 200 μm, which is close to the normal fracture strength range of diamond thin films (400-700 MPa). Conversely, the minimum principal stress and shear stress exhibit a decline as the film thickness increases. Raman characterization indicates that the surface of the diamond thin films has residual compressive stress. This residual stress decreases with increasing film thickness and cooling duration. After in-situ annealing at 600 °C in a hydrogen atmosphere, the stress-induced distortion in the films is alleviated, and there is a noticeable enhancement in the intensity of the diamond phase Raman peak. [ABSTRACT FROM AUTHOR]

To improve the magnetic properties of iron-based soft magnetic composites (SMCs), polytetrafluoroethylene (PTFE) with excellent heat resistance, electrical insulation, and extremely high electrical resistivity was chosen as an insulating coating material for the preparation of iron-based SMCs. The effects of PTFE content, compaction pressure, and annealing treatment on the magnetic properties of Fe/PTFE SMCs were investigated in detail. The results demonstrate that the PTFE insulating layer is successfully coated on the surface of iron powders, which effectively reduces the core loss, increases the resistivity, and improves the frequency stability and the quality factor. Under the combined effect of optimal PTFE content, compaction pressure, and annealing treatment, the iron-based SMCs exhibit a high effective permeability of 56, high saturation magnetization of 192.9 emu/g, and low total core losses of 355 mW/cm3 and 1705 mW/cm3 at 50 kHz for Bm = 50 mT and 100 mT. This work provides a novel insulating coating layer that optimizes magnetic properties and is advantageous for the development of iron-based SMCs. In addition, it also provides a comprehensive understanding of the relationship between process parameters and magnetic properties, which is of great guiding significance for scientific research and industrial production. [ABSTRACT FROM AUTHOR]

Copyright of Polymer Materials Science & Engineering is the property of Sichuan University, Polymer Research Institute 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.)

To investigate the influence mechanism of the annealing treatment on the intermolecular action of waxy crude oil, this study selected the molecular models of oil, wax, resin and asphaltene, and constructed the model system to imitate instead of the waxy crude oils by using the Materials Studio software, and revealed the influence mechanism of annealing treatment. Three main findings were made: 1) The basic molecular unit structure is the premise of phase transformation, and the different annealing times are the main factors affecting the phase transformation. 2) After annealing treatment, the conformation of molecular chain gradually changes from the initial straight chain to the curly state, and the change is most obvious at the lowest energy; in terms of system energy, the changes of Eval, Enon-bond and Etotal of the three oil samples all increase in different extent during the whole thermal process. 3) In terms of the radial distribution function (RDF) between the identical types of molecules and heterogeneous molecules of waxy crude oil, the accumulation of asphaltenes plays a leading role in the annealing process of waxy crude oil system, and the van der Waals force is the main force. [ABSTRACT FROM AUTHOR]

The micromechanical response of a Zr-based bulk metallic glass (BMG) annealed in air below and above its glass transition temperature was studied. Nano-sized particles in different states at different annealing temperatures were found on the surface of the samples, which were identified by energy-dispersive spectroscopy (EDS) as being CuNi elemental composition. The surface microhardness and nanoindentation creep behavior of the BMGs after annealed exhibited interesting results, at low annealing temperatures, the microhardness of the samples showed softening accompanied by poor creep resistance, while at high annealing temperatures, the hardness of the samples shows hardening and creep resistance was enhanced. The consequences of such a temperature-dependent dichotomy were intricately linked to element segregation, which led to microstructural fluctuations. A competing mechanism between the hardening effect of zirconia at the surface and the softening effect of elemental segregation in the formation of microporous structures inside the samples is proposed to account for the divergent mechanical properties due to the annealing temperature. This work presents helpful insights into microstructural changes and micromechanical properties of BMGs during annealing, as well as an experimental support for structural and property modulation of BMGs.

A composite of high-density polyethylene/ultra-high molecular weight polyethylene (HDPE/UHMWPE) was synthesized via a high-temperature melting process. We specifically examined the effects of annealing on the morphological and rheological properties of the composite. Using scanning electron microscopy and advanced rotational rheometry, we determined that annealing notably alters the composite’s microstructure, with a reduction in pronounced features post-treatment. Rheologically, UHMWPE content significantly enhanced mechanical properties, particularly in storage modulus (G′), loss modulus (G″), and complex viscosity (|η*|), which aligned with scaling law principles. Our findings highlight a distinct improvement in mechanical properties post-annealing, underscoring the potential of UHMWPE in enhancing polymer composite performance. The scaling laws relating G′, G″, and |η*| with UHMWPE were identified as follows: (1) pre-c e: G′ ∼ c 0.2, g″ ∼ c 0.07, |η*| ～ c0.07 and (2) post-c e: G′ ∼ c 1.20, g″ ∼ c 0.6, |η*| ∼ c 0.64, with a forward shift in c e noted after annealing. The addition of UHMWPE significantly enhanced the system’s properties, particularly after annealing. This study offers crucial insights into optimizing HDPE plastic films for enhanced durability and sustainability, ideally suiting them for eco-friendly agricultural uses.

BACKGROUND: Banana flour can provide a solution to people with gluten intolerance, as it is gluten‐free. Native banana flour may have limited functionality in certain applications. In this study, banana flour was modified by ultrasonic (US) and annealing (ANN) treatments at four incubation time spans, namely 12, 24, 36 and 72 h, separately or combined sequentially (US–ANN) to enhance the physicochemical and digestive properties. RESULTS: US led to exposed granular surfaces and damaged non‐starch components. Both treatments, at extended incubation time, increased crystallinity, resulting in a narrower starch gelatinization temperature range. The swelling power was significantly lower for ANN and US–ANN compared to US alone, providing a delay of gelatinization temperature. However, none of the treatments affected the gelatinization enthalpy. Furthermore, US increased peak viscosity, breakdown, final viscosity and setback whereas the opposite results were obtained for ANN and US–ANN. Additionally, US prior to ANN significantly increased the resistant starch (RS) content for annealing times over 24 h, especially for the US–ANN treatment for 72 h, which provided the highest RS content (49.3%) compared to ANN treatment for 72 h (44.0%) and native flour (36.3%). CONCLUSIONS: US prior to ANN treatment offers an alternative method to improve the functional and digestive properties of banana flour, extending the range of applications. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

This paper investigates the tensile properties and microstructures of Cu/Al clad sheets with an SUS304 interlayer after cryorolling and subsequent annealing and compares them with hot-rolled samples. The experimental results show that the inhibition of dynamic recovery by cryorolling enables the Cu/Al clad sheets to achieve a tensile strength of 302 MPa. After annealing, the tensile strength sharply drops to 159 MPa, while the elongation recovers to 29.0%. Compared with hot-rolled samples, the tensile strength of cryorolled samples is increased by 13.1% due to the effect of fine-grain strengthening. During the annealing process, the cryorolled samples exhibit improved elongation under a comparable strength with the hot-rolled samples, profiting from the higher degree of recrystallization and a higher proportion of annealing twins. The tensile properties of Cu/Al clad sheet with an SUS304 interlayer are strengthened by cryorolling and subsequent annealing, providing a new method for the fabrication of high-performance Cu/Al clad sheets. [ABSTRACT FROM AUTHOR]

Bi2Te3‐based materials play a crucial role in solid cooling and power generation, but the rapidly deteriorated ZT with rising temperatures above 450 K severely limits further applications. Here, this paper reports a novel preparation method of annealing treatment for molten ingot, which can enhance the thermoelectric performance of n‐type Bi2Te2.4Se0.6 in a wide temperature range. Instead of conventional halides, copper is adopted to regulate the carrier concentration and grain size to optimal levels. During the process of annealing at 573 K for 4 h, the number of twins significantly increases and the grains of Cu‐doped samples become larger and more oriented. These optimizations lead to higher carrier mobility with similar carrier concentration compared with the sample without heat treatment. The synergistic effects of Cu doping and annealing treatment realize a high average ZT of 0.89 within 300–600 K in n‐type Cu0.02Bi2Te2.4Se0.6. Combined with p‐type (Bi,Sb)2Te3, the fabricated thermoelectric device exhibits a high conversion efficiency of 6.9% at a temperature difference of 300 K. This study suggests that annealing treatment is a simple and effective scheme to promote the applications of n‐type Bi2(Te,Se)3 in a wide temperature range. [ABSTRACT FROM AUTHOR]

Silk sericin (SS)–based hydrogels show promise for wound healing due to their biocompatibility, moisture regulation, and cell proliferation properties. However, there is still a need to develop green crosslinking methods to obtain non-toxic, absorbent, and mechanically strong SS hydrogels. This study investigated the effects of three green crosslinking methods, annealing treatment (T), exposure to an absolute ethanol vapor atmosphere (V.E), and water vapor (V.A), on the physicochemical and mechanical properties of SS and poly (vinyl alcohol) (PVA) biohydrogels. X-ray diffraction and Fourier-transform infrared spectroscopy were used to determine chemical structures. Thermal properties and morphological changes were studied through thermogravimetric analysis and scanning electron microscopy, respectively. The water absorption capacity, mass loss, sericin release in phosphate-buffered saline (PBS), and compressive strength were also evaluated. The results showed that physical crosslinking methods induced different structural transitions in the biohydrogels, impacting their mechanical properties. In particular, V.A hydrogen presented the highest compressive strength at 80% deformation owing to its compact and porous structure with crystallization and bonding sites. Moreover, both the V.A and T hydrogels exhibited improved absorption capacity, stability, and slow SS release in PBS. These results demonstrate the potential of green physical crosslinking techniques for producing SS/PVA biomaterials for wound healing applications. [ABSTRACT FROM AUTHOR]

We discussed the decrease in residual stress, precipitation evolution, and mechanical properties of GH4151 alloy in different annealing temperatures, which were studied by the scanning electron microscope (SEM), high-resolution transmission electron microscopy (HRTEM), and electron backscatter diffraction (EBSD). The findings reveal that annealing processing has a significant impact on diminishing residual stresses. As the annealing temperature rose from 950 to 1150°C, the majority of the residual stresses were relieved from 60.1 MPa down to 10.9 MPa. Moreover, the stress relaxation mechanism transitioned from being mainly controlled by dislocation slip to a combination of dislocation slip and grain boundary migration. Meanwhile, the annealing treatment promotes the decomposition of the Laves, accompanied by the precipitation of μ-(Mo6Co7) starting at 950°C and reaching a maximum value at 1050°C. The tensile strength and plasticity of the annealing alloy at 1150°C reached the maximum (1394 MPa, 56.1%) which was 131%, 200% fold than those of the as-cast alloy (1060 MPa, 26.6%), but the oxidation process in the alloy was accelerated at 1150°C. The enhancement in durability and flexibility is primarily due to the dissolution of the brittle phase, along with the shape and dispersal of the γ′ phase. [ABSTRACT FROM AUTHOR]

In this work, the microstructure, and mechanical properties of cold-rolled low-density multi-principal-element Fe-30Mn-10Al-1.57C-2.3Cr-0.3Si-0.6Ti (wt.%) specimens were systematically investigated by annealing under different conditions. The microstructural evolution and strengthening mechanism were also examined. Results from x-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and electron backscatter diffraction (EBSD) analyses confirmed that carbides were composed of TiC and κ-carbides. As the annealing temperature increased, both the volume fraction of κ-carbides and yield strength (YS) of the alloys decreased. TEM images indicated a pile-up of dislocations around carbides and boundary of twins. The increase in annealing temperature to 450 °C led to best mechanical properties of specimens with σ0.2% = 1270.28 MPa, Rm = 1318.67 MPa, and ε = 19.47%. Moreover, YS decreased by 9.28% and TE increased by 192.78%. Notably, the density of the as-obtained alloy reached 6.58 g/cm3, a value 15.6% lower than that of conventional steel. In sum, these findings are promising for future applications of low-density alloys. [ABSTRACT FROM AUTHOR]

Ductile iron with different Ni contents (0–10%) was successfully fabricated through horizontal continuous casting technology, and the effects of Ni content on ductile iron's microstructure and mechanical properties were investigated. The results showed that the Ni addition affected the diffusion of carbon atoms, altering the phase constituents during solid-state transformation. The ductile iron with Ni amounts less than 2% was composed of spheroidal graphite and ferrite. The addition of the 2% Ni addition led to more than 40% pearlite in the matrix. When the Ni content exceeded 6%, bainite and martensite were detected, which enhanced strength significantly but deteriorated ductility. Annealing treatment facilitated the dissolution of carbides and increased ferrite fraction, contributing to the improvement of ductility. The as-annealed sample with 8% Ni showed an ultimate tensile strength of 1057 MPa and an elongation of 4.6%. [ABSTRACT FROM AUTHOR]

In this paper, <123>-oriented aluminum single crystals were deformed by unidirectional torsion followed by annealing treatment. The microstructure evolution and static recrystallization behavior of aluminum single crystal samples after annealing were characterized by electron backscatter diffraction (EBSD). The results show that the lattice rotation occurs in the aluminum single crystal, and the deformed matrix was composed of microbands (MBs) parallel to the active slip plane {111} during torsional deformation at room temperature. The mutual absorption of dislocations promotes the dislocation accumulation, which results in the lattice rotation and orientation scattering of the deformed aluminum single crystals. When the annealing temperature is 500 ℃, the nucleation and growth of secondary recrystallization grains significantly increase due to the accelerated grain boundary migration rate. The preferential growth of secondary recrystallization grains with misorientation of 20°-45° high-energy grain boundaries, resulting in a continuous growth of the grain size to about 1 mm. The nucleation of recrystallizations was rotated 20°-60° around the <111>, <123> and <122> directions by adjacent deformed matrix, and the 30°-50°<111> orientation relationship gradually dominates with the increasing of strain and annealing temperature. [ABSTRACT FROM AUTHOR]

In this study, thin films of Cerium Oxide CeO2 were fabricated using the sol–gel technique and deposited onto a glass substrate. The annealing process was carried out at various temperatures ranging from 200 to 600  ° C  to investigate the structural, morphological, and optical properties of the films and their interrelations. X-ray diffraction (XRD) patterns revealed the crystalline nature of the prepared films, with film quality exhibiting enhancement with increasing annealing temperature. The average crystallite size, dislocation density, microstrain, and lattice constant were determined from XRD patterns. Higher annealing temperatures were found to increase the crystallite size values from 4.71 to 15.33 nm and decrease the dislocation density and microstrain of the unit cell. Scanning electron microscope (SEM) images illustrated the uniformity of the films, presenting a spheroid shape. Optical properties such as transmittance, absorbance, reflectance, the direct band gap, extinction coefficients, the refractive index, and optical conductivity were assessed using optical measurements. The direct optical band gap of the CeO2 film was observed to decrease from 3.99 to 3.75 eV with increasing film thickness. Using the Wemple and DiDomenico (WDD) single-oscillator model, dispersion energy parameters were calculated based on the refractive index. The nonlinear optical properties of the CeO2 thin films were evaluated using these dispersion energy parameters. The improvement of optical parameters holds significance in standardizing CeO2 thin films for various optoelectronic applications. [ABSTRACT FROM AUTHOR]

This study evaluates the mechanical and electrical properties of copper-clad aluminum (CCA) wire prepared with a total cross-section reduction of 89% through a multistage cold drawing process and subjected to annealing at various temperatures. In addition to the CCA wire, individual samples of oxygen-free copper and aluminum, drawn with a cross-sectional reduction of 50%, were annealed under the same temperature conditions to enable a comparative analysis. Tensile tests for strength and elongation measurements were conducted, while electrical conductivity was assessed through resistivity tests. SEM and EDS analyses were performed to examine the diffusion thickness and the composition of intermetallic compounds generated at the Al/Cu interface of CCA wire. The tensile strength of the CCA wire decreased and its elongation increased up to 250 °C, after which were maintained. As the annealing temperature increased, intermetallic compound layers of Al2Cu, AlCu, and Al4Cu9 were formed at the Al/Cu interface of the CCA wire, and their thickness increased. Electrical conductivity reaches a maximum at 200 °C and then continuously decreases, showing a negative linear correlation with an increase in the diffusion layer thickness of intermetallic compounds. The study confirmed that cold-drawn CCA wire achieves stable mechanical properties and maximum electrical conductivity at the optimal annealing temperature.

Although titanium dioxide (TiO2) has a wide range of potential applications, the photocatalytic performance of TiO2 is limited by both its limited photoresponse range and fast recombination of the photogenerated charge carriers. In this work, the preparation of nitrogen (N)-doped TiO2 accompanied by the introduction of oxygen vacancy (Vo) has been achieved via a facile annealing treatment with urea as the N source. During the annealing treatment, the presence of urea not only realizes the N-doping of TiO2 but also creates Vo in N-doped TiO2 (N-TiO2), which is also suitable for commercial TiO2 (P25). Unexpectedly, the annealing treatment-induced decrease in the specific surface area of N-TiO2 is inhibited by the N-doping and, thus, more active sites are maintained. Therefore, both the N-doping and formation of Vo as well as the increased active sites contribute to the excellent photocatalytic performance of N-TiO2 under visible light irradiation. Our work offers a facile strategy for the preparation of N-TiO2 with Vo via the annealing treatment with urea. [ABSTRACT FROM AUTHOR]

To obtain a high-entropy alloy characterized by high strength and plasticity, (NiCoV) 100-x Ga x (x ​= ​0, 5, 7) was successfully prepared, cold-rolled, and heat-treated. The microstructure was analyzed to correlate Ga content with the performance of the system. The addition of Ga can produce alloying effects, including solid solution strengthening effect, second phase precipitation strengthening effect, and layer misalignment energy reduction effect. The experimental results show adding Ga elements can enrich Ni, Co, V, and Ga above the grain boundaries, causing the alloy to produce annealed twins inside. The alloy is strengthened mainly by precipitation, and the formation of the precipitation phase effectively enhances the strength of the alloy. The low stacking fault energy promotes the toughening of NiCoV but makes the plasticity of the alloy decrease. Still, the formation of annealed twins effectively increases the plasticity, which makes the alloy harder but does not reduce the plasticity too much. By comparing the experimental properties, (NiCoV) 93 Ga 7 showed the best mechanical properties at the annealing temperature of 900 ​°C, yield strength, tensile strength and elongation of 906 ​MPa, 1321 ​MPa and 21.36 ​%, respectively. [ABSTRACT FROM AUTHOR]

It is common to use heat treatment process to control the microstructure of additive manufacturing parts and improve the mechanical properties. However, there are few reports about the control of microstructure properties of WAAM hybrid inter-layer hammering fabricated parts by heat treatment. In this study, the effect of annealing on microstructure and mechanical properties of inter-layer hammering hybrid wire arc additively manufactured aluminum alloy was studied. The ratio variation of fine grain (FG) and coarse grain (CG) regions, grain size and dislocations were analyzed, and the strength-plasticity mechanism was revealed. The results shown that with the increase of annealing temperature, the ratio of FG and CG region changed from 4:1–1:5, grain growth and recrystallization happened in FG and CG regions, respectively, dislocations mostly retained in FG region and released in CG region. With the introduction of annealing and the increase of annealing temperature, the strength of hybrid manufactured samples gradually weakened while the plasticity first improved and then reduced. The best tensile properties of ultimate tensile stress 366 MPa and elongation 29.2% were achieved at 180 °C annealing. Compared with as-deposited sample, the synergistic enhancement of strength and plasticity in annealed samples is owing to dislocation strengthening, grain refinement, and heterogeneous structural strengthening. Compared with hammered sample, the strength retained and significant improved in plasticity of annealed sample, owing to dislocation released, grain refinement and heterogeneous structural. • The variation ratios of FG and CG regions were studied. • Superior strength-ductility was achieved with annealing treatment. • The effect of annealing on strengthening mechanism was revealed. [ABSTRACT FROM AUTHOR]

A systematic study was conducted on the impact of annealing treatments on the microstructure and properties of cold-rolled Ti50Ni47Fe3 alloys using optical microscopy, scanning electron microscopy, electron backscattered diffraction, and an electronic universal testing machine. It was found that, during low-temperature annealing (400 °C and 500 °C), the annealing time had no significant effect on the microstructure or properties of the Ti50Ni47Fe3 alloy. Only elongation (δ) increased with the increase in the annealing time, and the grain orientation of the Ti50Ni47Fe3 alloy was <111>//RD (rolling direction). When annealing at medium–high temperature (600 °C), as the annealing time increased, recrystallization and grain growth processes occurred, resulting in a continuous decrease in strength and an increase in δ. Meanwhile, it was found that the grain orientation of the cold-rolled Ti50Ni47Fe3 alloy changed from <111>//RD during the recovery and recrystallization processes to <101>//RD after the grain growth process. The orientation distribution function cross-section φ2 = 45° results indicate that the texture was mainly distributed along the γ orientation line (φ1 = 0~90°, Φ = 54.7°, φ2 = 45°). When annealed at 400 °C and 500 °C, the texture of the Ti50Ni47Fe3 alloys was (111)[uvw]. When the annealing treatment was 600 °C for 120 min, a (110)[uvw] texture occurred. Additionally, ductile fracture occurred in all specimens, and the crack origin was located on one side of the fracture surface, with obvious "Y"-shaped propagation. This article studied annealing treatments of cold-rolled Ti50Ni47Fe3 alloys, providing corresponding theoretical guidance for subsequent production applications. [ABSTRACT FROM AUTHOR]

Austenitic stainless steel has high toughness and plasticity; however, it tends to exhibit low yield strength, which severely limits the widespread application of this steel. It can be strengthened by cold working; however, this will cause many defects in the structure. Therefore, annealing treatment must be carried out before use. In this paper, the effects of annealing treatment at different temperatures and times on the microstructure and mechanical properties of cold-rolled 305 stainless steel sheet were studied and the theoretical mechanism was further analyzed to provide better theoretical guidance for production and application. It was found that the microstructure grains obtained by annealing at 850 °C for 30 s were finer and more uniform, and the mechanical properties were also the best, which met the requirements of strong plasticity. Therefore, the rolling and annealing experiments could be carried out again under this annealing condition, and the requirements of the finished product could be finally obtained. At this time, the thickness of the plate was about 0.15 mm, the yield strength was 1238 MPa, and the permeability was below 1.02, which met the production requirements of the metal mask plate. [ABSTRACT FROM AUTHOR]

Al wires with different deformation were obtained by cold-drawing and annealing treatment. The microstructure, mechanical, and electrical properties of the wires annealed at different temperatures and times were studied using SEM, universal testing machine, and DC resistance tester. The results indicate that as the annealing temperature and time increase, the UTS of Al decreases, while the EL and EC increase simultaneously. During the annealing procedure, recrystallization is observed to begin at 300 ℃ and complete at 350 ℃. Compared with the beginning of recrystallization, the recrystallized grain diameter increases from 11.34 μm to 20.59 μm, while the UTS decreases by 24.1 %, the EL increases by 74 %, and the EC increases by 3 %. When annealed at 315 ℃ for 1h, the recrystallization begins in the samples with 90 % deformation, and completes when the annealing time is increased to 4.5 h, the grain diameter increases from 7.67 μm to 20.71 μm; though the tensile decreases by 24.3 %, the EL and EC increase by 97.5 % and 2.8 %, respectively.

High Nb–TiAl alloys fabricated using laser powder bed fusion (LPBF) exhibit a metastable α2 phase due to the rapid cooling rate of the LPBF process. However, the understanding of the structural transformation behavior in LPBF-fabricated high Nb–TiAl alloys remains limited. In this work, a high Nb–TiAl alloy with a nominal composition of Ti–48Al–2Cr–8Nb (at. %) was additively manufactured using LPBF. The structural transformation from metastable α2 phase to γ phase was then studied by the in-situ high-temperature x-ray diffraction (XRD), in-situ heating transmission electron microscopy (TEM) and differential scanning calorimetry (DSC). Furthermore, the phase composition and microstructure of the samples annealed at different temperatures were determined by XRD and electron backscatter diffraction (EBSD). Our findings demonstrate that the α2 phase in LPBF-fabricated high Nb–TiAl alloy remains stable up to 873 K, after which it decomposes and forms fine γ lamellar colonies along with a disordered γ′ phase as an intermediate phase. Notably, the transition from α2 to γ′ phase is reversible. In contrast, the formation of the γ phase is irreversible and persists down to room temperature. It is also found that the changes in grain size and phase composition of the LPBF-fabricated high Nb–TiAl alloy have a significant impact on its hardness. This study provides valuable insights into the structural transformation behavior of additively manufactured high Nb–TiAl alloys by LPBF, offering guidance for regulating their structure and properties.

The 0.05 mm-thick 304 stainless steel foil was annealed within the temperature range from 950℃-1100℃ for 10 minutes to obtain different microstructures. And micro-deep drawing experiments of stainless steel foils with different tissue structures were conducted to obtain relevant material forming properties influenced by dimensional effects. On this basis, the influence of the microstructure characteristics on the forming performance of 304 stainless steel foil and the quality of the cup formed by using micro-drawing was studied, and its mechanism was discussed. It can be seen from the results that the stainless steel foil annealed at 950℃ exhibits poor forming performance, and the wrinkle phenomenon of the deep-drawn cup is obvious. At the annealing temperature of 1050℃, the quality of the deep drawing cup is significantly improved. When the annealing temperature reaches 1100℃, with the increase of the annealing temperature, the crystal grains size increase sharply, and the coarse-grain effect causes the uneven plastic deformation effect to be obvious. Besides, the drawing quality is obviously deteriorated. The observation of the microstructure of the deep drawing cup shows that the forming effect of the drawing cup is poor due to the rolling defects and the coarse grain effect. The 304 stainless steel drawing cup annealed at 1050℃ enjoys the best forming effect.

Cold-working combined with annealing is frequently used to enhance strength of traditional alloy materials. However, this thermal-mechanical processing is not adapted to the preparation for some near net shape parts. In this paper, a dual-phase Ni39.3Al15.7Fe45 eutectic medium entropy alloy (EMEA) was prepared by vacuum arc melting and abnormal annealing-induced strengthening is demonstrated and analyzed via XRD, SEM, EDS, TEM and room temperature tensile testing. It is found that the Ni39.3Al15.7Fe45 EMEA is composed of FCC solid solution phase and BCC phase. After annealing, ordered L12 phase precipitated from FCC solid solution, which induces a significant increment of tensile strength and a weak decrease of tensile plasticity. The tensile strength and elongation are 991 MPa and 24.1 % at as-cast state, the tensile strength and elongation are 1279 MPa and 22.4 % after annealing at 700 °C for 1 h.

To enhance the friction and wear properties of alloys, AlCrTiVNbx high-entropy alloys (HEAs) with various Nb contents were prepared using the arc melting technique and then annealed at 1000 °C for 2 h. The microstructure and hardness changes in the AlCrTiVNbx (x = 0.3, 0.4, and 0.5) HEAs after casting and annealing were studied via scanning electron microscopy, X-ray diffractometry, optical microscopy and the Vickers hardness test. The MFT-EC400 ball disc reciprocating friction and wear tester was used to investigate the wear resistance of the HEAs before and after annealing. The results show that the annealed AlCrTiVNbx HEAs changed from a single-phase structure to a multi-phase structure, and the content of the face-center cubic (FCC) phase and hexagonal close-packed (HCP) phase further increases with the increase in Nb content. The hardness value of the annealed HEAs is greatly enhanced compared with the casting state, and the hardness of the Nb0.5 HEA is increased from 543 HV to 725 HV after annealing. The wear resistance of the alloys after the annealing treatment is also greatly improved, among which Nb0.5 has the best wear resistance. The average friction coefficient of Nb0.5 is 0.154 and the wear rate is 2.117 × 10−5 mm3/(N·m). We believe that the precipitation strengthening after the annealing treatment and the lubrication effect of the FCC phase are the reasons for the significant improvement in wear resistance. The morphology of the samples indicates that the wear mechanism of the alloy includes adhesive wear, abrasive wear and a certain degree of oxidation wear. [ABSTRACT FROM AUTHOR]