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The study of recrystallization and grain growth in annealed metals has been extensively investigated using various computational approaches, with Monte Carlo (MC) simulations proving particularly effective. This research highlights the application of the MC method in simulating microstructures that closely resemble experimentally observed ones. The experimental microstructures were obtained from a 50% cold-worked Al–4% Cu (Duralumin) alloy, annealed at different conditions. The Metropolis algorithm was employed to simulate the microstructures using a two-dimensional Potts model on a square lattice. The simulated results strongly correlate with the actual microstructures, validating the effectiveness of the MC method in exploring grain growth phenomena. This study underscores the potential of MC simulations as a robust tool for investigating recrystallization and grain evolution in annealed metals.

The paper deals with axial segregation in unsteady diffusion dominated directional solidification from melt of a binary alloy in a finite cylindrical ampoule. The study focuses on the influence of the finite length of the ampoule on the concentration profile in a crystal obtained in a microgravity environment. The results are compared to those reported by Kim et al. [J. Crystal Growth183, 490 (1998)] for an infinite crystal. Numerical simulations are performed for two different situations: the initial transient solidification when the melt is uniform in composition, and the multipass solidification when the crystal is grown from the melt, formed by re-melting a crystal with an initial axial composition profile.

An experimental investigation is undertaken to examine the possibility of producing ultra-fine grained bulk material through high-speed impact compression followed by annealing. A gas gun was employed to impose high-rate deformation on oxygen-free high-conductivity copper specimens to 90% strain. Samples were also quasi-statically compressed to identical final strains and similar heat treatment. Results show that after impact compression, grain boundaries widen and become less sharply defined, and many narrow twins are formed. For dynamic loading, grain boundary slip appears to accompany dislocation movement. Two dislocation characteristics were identified and the dislocation density was lower than that in samples compressed quasi-statically. Small dislocation loops were also observed. Portions of grains in specimens subjected to impact were mechanically broken into sizes less than 1 μm before annealing. The microhardness of impacted and statically compressed samples increased respectively by HV50 and HV60. After annealing at 190°C for 1 hour, ultra-fine grains with grain sizes ranging from 40∼200 nanometers were observed in impacted samples. This study highlights the potential of utilizing impact compression to produce bulk material with ultra-fine grains.

Microstructure evolution and texture formation in low carbon CSP steel were observed by means of metallgraphic, TEM, and SEM equipped with electron back scattered diffraction (EBSD) system. The influence of large particles and fine carbonitrides precipitates on recrystallization and texture formation during the annealing procedure was analyzed with Small Angle X-ray Scattering (SAXS) technique in the steel. It was found that the fine precipitates present in the steel have shown ability to stimulate recrystallization nucleation and transformation during deformation, but hard to accelerate recrystallization growth because of grain boundary pinning effects in the steel. Compared with the conventional low carbon steel, the recrystallization texture and microstructure of the CSP steel show distinct character, and thus modify the mechanical behaviour of the final products.

Recrystallization behavior of a nickel-base single crystal superalloy cold-deformed by compression has been investigated. The effects of plastic strain, annealing temperature and annealing time have been studied, and recrystallization diagram has been obtained. It has been found that a very strong dependence upon temperature is evident. For the single crystal superalloy with 4.5% strain, full recrystallization has been observed when annealing at 1300°C for 1h, surface recrystallization at 1250°C for 1h, cellular recrystallization at 1150°C for 1h and no recrystallization at 1100° for 1h. With the drop of temperature, the volume fraction of γ′ phase increases, which incrementally restricts recrystallized boundary migration. With the increasing of annealing time or strain, the sensitivity of recrystallization increases. Recrystallization tendency of standard- heat-treated superalloy is weaker than that of as-cast single crystal superalloy, because standard heat treatment reduces the microsegregation, lowers the eutectic amount and forms homogeneous γ1 phase distribution, which decrease preferential nucleation site of recrystallized grain and increase the resistance of boundary migration of recrystallization.

Microstructural evolution and flow behavior of twin-roll cast AZ41 magnesium alloy during hot compression were characterized by employing deformation temperature of 300°C, 350°C and 400°C, and strain rate ranging from 10^-3 to 10^-2s^-1. When compressed at different temperature (300°C, 350°C and 400°C) and strain rate (10^-3 and 10^-2s^-1) all stress strain curves showed a flow softening behavior before strained to 0.51 due to dynamic recrystallization, even though concurrent twinning was quite active. Twinning contributed to the flow hardening behavior appeared during the end of hot compression (ε > 0.51) at a strain rate of 10^-2s^-1 and elevated temperature (300°C, 350°C and 400°C) in spite of the softening effect of concurrently occurred dynamic recrystallization. TEM image showed that discontinuous recrystallization occurred when deformed at elevated temperature as high as 400°C and the strain rate ranging from 10^-2 to 10^-3s^-1. It is suggested that dislocation slip, twinning and recrystallization develop in a cyclic mode from initial stage to the end of hot compression.

Flow stress behavior during initial stage of hot compression of twin-roll cast ZK60 magnesium alloy was characterized by employing deformation temperature of 300°C and 400°C, and a given strain rate of 10^-2s^-1. A stress drop during initial stage of hot compression at 300°C, generally led by dynamic recrystallization, was found to be attributed to twinning, correspondingly to dynamic recrystallization as deformation temperature was raised to 400°C.

Large-size and high-quality anthracene single crystals were prepared simply by solution technique. The basal planes correspond to (001) face and two large lateral faces of the anthracene crystals determined to be the (100) plane can also be obtained. The optical properties of the obtained anthracene single crystals were studied. The results indicate that anthracene can be a good window material up to 410 nm as the transmittance of the obtained crystal is around 70% from 800 nm to 410 nm and the band gap energy is 3.02 eV. The dielectric components in x-, y- and z-directions of the obtained crystals were extracted by fitting the results from spectroscopic ellipsometry and the results indicate the dielectric anisotropy of anthracene single crystals. The reflectivity calculated from the permittivity is close to the measured results.

The cold-rolled pure copper sheets were annealed with and without a high magnetic field of 12 T. The results showed that the magnetic annealing could promote the formation of the initial recrystallized cube texture. The magnetic annealing did not dramatically change the final annealing textures, but the intensity of the recrystallized cube texture is obviously different. The differences of the recrystallized cube orientation intensity between the specimens with and without the field annealing may be attributed to the effects of the magnetic field on the mobility of grain boundaries.

The aim of our investigation is focused on studying the effect of dopant dose loss during annealing treatments on heavily doped surface layers, obtained by recoil implantation of antimony in silicon. We are interested particularly by the increase of sheet resistance consequently to the shallow junctions obtained at the surface of substrate and the contribution of the dopant dose loss phenomenon following the high concentration of impurities at the surface. In this work, we report some quantitative data concerning the dopant loss at the surface of silicon implanted and its dependence with annealing treatments. Electrical measurements associated with Rutherford backscattering (RBS) technical analysis showed interesting values of sheet resistance compared with classical ion implantation and despite dopant dose loss phenomenon.

Silicon (Si) nanocrystals have been considered a good candidate for flash memory device and nanophotonic applications. The fabrication of nanocrystal memory is to form uniform, small size and high density quantum dots. In this study, nanometer-scale silicon quantum dots have been fabricated on ultrathin silicon oxide layer using amorphous silicon (a-Si) deposition followed by various annealing treatments. The a-Si layers were crystallized using furnace annealing, laser annealing and rapid thermal annealing (RTA). After annealing to form nanometer-sized crystallites, silicon wet etch was carried out to isolate the nanocrystals. The size, uniformity and density of the nanocrystals were successfully controlled by different annealing treatments. The mean dot height and mean dot diameter is 1–5 nm and 2–5 nm, respectively. Lateral growth of the silicon dots was further controlled by systemic variations of the annealing conditions. It is found that the annealed a-Si films exhibit room temperature visible photoluminescence (PL) resulting from the formation of nanometer-sized crystallites. Selective wet etch and Secco-etch treatment increased the PL efficiency that is useful for nanophotonics applications. The feasibility of quantum dot formation using ultra thin amorphous Si films is demonstrated in this work.

This study is on a new approach for fabrication of poly-Si thin films. Aluminum-induced crystallization of a-Si film has been achieved by thermal annealing only at around 400 °C. The Experimental results reveal that the Al on top of a-Si arrangement has more evident effect in crystallization enhancement than that with Al under a-Si, and the resultant poly-Si films show preferred (400) crystal orientation. It is verified that aluminum can cause lateral crystallization of a-Si film. No preferred orientation was noticed from lateral crystallization samples.

A novel Sr₂Al₂SiO₇:Eu${}^{2+}$, Dy${}^{3+}$ long-persistent luminescence (LPL) glass–ceramic has been successfully synthesized by the recrystallization-melting method in the SrO-Al₂O₃-SiO₂-B₂O₃-Li₂ O glass system. The glass–ceramic form enhances the plasticity of the material compared to traditional Sr₂Al₂SiO₇:Eu${}^{2+}$, Dy${}^{3+}$ phosphorescence powders. Additionally, the Dy${}^{3+}$ ions serve a dual role as fluorescence emission centers and sensitizers for afterglow. By controlling the concentration of Dy${}^{3+}$, the characteristic fluorescence intensity can be adjusted to achieve color-tunable photoluminescence. Besides, Dy${}^{3+}$ ions, as trap centers, capture the electrons, resulting in a longer afterglow than the Eu${}^{2+}$ singly doped sample. After exposure to ultraviolet light, the initial brightness intensity of the Dy:Eu = 16:1 sample increases to 1525 mcd/m², and the emission lasts for 30 min. These optimized bulk materials, with unique luminous properties, have potential applications in future optoelectronic devices.

Thermal behaviors of tungsten coating of 0.5 mm thick with multi-layers interface of tungsten (W) and rhenium (Re) coated on CFC (CX-2002U) substrate by vacuum plasma spraying (VPS) technique were examined by annealing with an electron beam thermal load facility between 1200 °C and 2000 °C. Change of the microstructure was observed and its chemical composition was analyzed by EDS after annealing. It was observed that remarkable recrystallization of VPS-W occurred above 1400 °C. The structure of the multi-layers of W and Re become obscure by the mutual diffusion of W, Re and C above 1600°C and finally disappeared after annealing at 2000 °C for one hour. Very hard tungsten carbides are formed at the interface above 1600 °C and they were broadening with increasing annealing temperature and time.