Influence Of Annealing Treatment Research Articles

Hexagonal ZnTiO3 single-crystalline films on α-Al2O3 substrates: Structural and photoelectric properties

Hexagonal ZnTiO3 (h-ZnTiO3) films with stoichiometric were deposited on α-Al2O3 substrates using pulsed laser deposition (PLD) method and post annealing process. The effect of oxygen partial pressure on Zn/Ti atomic ratio, as well as the influence of annealing treatment on the structural and optical properties of the films were investigated in detail. The optimum h-ZnTiO3 film was deposited under 5 Pa oxygen partial pressure and annealed at 800°C, and it exhibited excellent crystalline quality and an optical band gap of 3.72 eV. A photodetector based on the film was fabricated, and its photoresponsivity was approximately 0.18 mA/W under 308 nm ultraviolet light irradiation. This demonstrates that as a wide bandgap semiconductor material, h-ZnTiO3 has potential applications in the field of devices.

Influence of annealing treatment on performance of 4H–SiC SBD irradiated by heavy ions under room temperature and low temperature

The influence of the annealing treatment on the performance of commercial 4H–SiC Schottky barrier diodes (SBDs) subjected to heavy ion irradiation under room temperature (RT) and low temperature (LT) are presented. Experimental results confirm that annealing treatment effectively eliminates defects and interface states caused by heavy ion irradiation, particularly for 4H–SiC SBD under LT irradiation. Increasing the annealing temperature leads to the slight improvement in forward current, leakage current and breakdown voltage. However, the annealing process may result in the formation of Ti and Si compounds at the interface between the Schottky metal and SiC, as well as a significant number of vacancies. Combined with Technology Computer Aided Design (TCAD) simulations, it is concluded that the interface trap charge concentrations exceeding 1 × 1012 cm−2 significantly impact the breakdown characteristics of 4H–SiC SBDs.

Influence of annealing treatment on grain growth, texture and magnetic properties of a selective laser melted Fe-6.5 wt% Si alloy

The high-density Fe-6.5 wt% Si soft magnetic alloy samples were prepared using selective laser melting (SLM) technology. Annealing treatments with different temperatures were employed to promote grain growth. The microstructure, texture and magnetic hysteresis loops were characterized, aiming to investigate the relationship between microstructure and magnetic properties. The as-printed Fe-6.5 wt% Si alloy had weak texture and low density of ordered phases, and was featured by coarse grains in the top-view section and columnar grains in the side-view section. After annealing at 800 °C–1000 °C, the textures were slightly weakened, while the grain growth was not significant. Increasing the annealing temperature to 1100 °C led to abnormal grain growth behaviors. The grains of the as-printed Fe-6.5 wt% Si alloy showed randomly abnormal growth behaviors rather than oriented growth, which may be related to the low stored energy and initial size advantage before annealing. After annealed at 1100 °C for 1 h, the abnormal grain growth and the formation of large Goss ({110}<001>) and Cube ({100}<001>) grains resulted in microstructure coarsening and texture optimization. Thus, the corresponding ring-shaped sample exhibited excellent magnetic performance. The magnetic induction B8 is 1.21 T, the maximum relative permeability is 14.71 × 103 and the core loss P10/50 is 11.69 W/kg.

Probing the electrical performance improvement of FET device based on multilayer MoS2 material

The process quality of material and device can be evaluated by the electrical performance. In this paper, the multi-layer MoS2 material and nickel (Ni) metal were used as channel and electrodes of FET device, which can be fabricated by the electron beam lithography and evaporation processes. The morphology, structure, component and spectral characteristic of multilayer MoS2 material and device were characterized by optical microscope, Raman spectrometer and scanning electron microscope (SEM), and the fabrication feasibility was also discussed. Meanwhile, the electronic performance of device was tested and analyzed by probe table and semiconductor parameter analyzer, and the influence of annealing treatment can also be explored. The contact resistance of device decreases after annealing, current switching ratio increase by one order of magnitude, output characteristic curve shows linear, and the electrical performance can also be improved, which can provide the research guidance for the electronic device based on multilayer MoS2 material.

Effect of annealing treatment on the magnetic properties with wide temperature range of Co-doped FeSi soft magnetic composites

Fe-Si-Co soft magnetic composites (SMCs) coated with silicone resin were successfully prepared in this work. The influences of annealing treatment on the temperature/frequency-dependent behaviors of magnetic properties for SMCs were studied by microstructureanalysis and loss separation. Results show that the core loss of Fe-6.5Si-1.0Co SMCs gradually decreases with annealing temperatures rising from 500 °C to 700 °C when measured at 50 kHz, while the core loss of Fe-6.5Si-3.0Co SMCs first decreases then increases. Meanwhile, the effective permeability Fe-6.5Si-1.0Co and Fe-6.5Si-3.0Co SMCs are significantly improved. Simultaneous optimization for core loss and effective permeability benefits from the residual stress relief and defect elimination induced by annealing. Fe-6.5Si-1.0Co SMCs annealed at 700 °C shows excellent comprehensiveperformances with core loss of 766.7 mW/cm3 and effective permeability of 112.3 measured at 0.1 T / 50 kHz. While annealing at excessive temperature causes the phase transition and change in resistance of silicone-resin coatings, leading to the rapid deterioration of the magnetic performances. As for the temperature characteristics, the Fe-Si-1.0Co SMCs also exhibits good stability for effective permeability and negative correlation for core loss with the measuring temperature ranging from −25 °C to 125 °C. This work may provide some theoretical support for the wide temperature domain application of the Co-doped FeSi SMCs.

Effect of the Annealing Treatment on the Microstructure and Corrosion Resistance of a Cu-Al-Ni Alloy

The influence of annealing treatment on the microstructure and the corrosion behaviour of a complex bronze Al-Ni alloy was analysed. The microstructural characterization after thermic treatment shows that the retained β-phase disappears and the KII-phase undergoes a spheroidization process. Moreover, there is an augmentation of K-phase precipitates within the α-phase, particularly KIV and KV, which homogenizes the distribution of alloying elements between the phases. The corrosion behaviour was investigated by means of selective corrosion tests, potentiodynamic measurements, and electrochemical impedance spectroscopy. All of the experiments showed that thermic treatment greatly improves the corrosion resistance of the alloy. As such, annealing treatment influences a microstructure to be more dealloying resistant, which allows the development of a more protective air-formed passive film. On the other hand, the lower current registered after anodic peaks and Electrochemical Impedance Spectroscopy data seem be correlated with a more protective layer formed on annealed material. As such, this protective character is due to a greater incorporation of Al3+, Ni2+ and Cu2+ in the passive film, as revealed by X-ray Photoelectron Spectroscopy results.

Properties study of ZnO films prepared by ALD

ZnO and B-doped ZnO(BZO) films were deposited on the glass substrate by atomic layer deposition (ALD) method. The influence of annealing treatment and B-doping on properties of ZnO films was investigated. The results indicated that all samples have hexagonal wurtzite structure with (002) preferential orientation and the film crystallinity is improved with increasing deposition temperature and annealing temperature. The resistivity decrease with the increase of annealing temperature. The incorporation of B increases the electrical properties of the ZnO film.

Influence of Annealing Treatment on Microstructure and Properties of Ni-Rich NiTi Alloy Coating Prepared by Laser Cladding.

NiTi alloys are widely known for their shape memory effect and super-elasticity. In this study, the laser cladding method was applied to prepare Ni-rich NiTi alloy coatings on 316L stainless steel substrate. The microstructure, phase composition, element distribution and phase transformation behavior of the coatings were investigated in as-fabricated and annealing-treated states. The results indicated that the recrystallized microstructure obtained and the content of Ni3Ti and Ti2Ni phases increased significantly with a rising annealing temperature. Annealing treatment also induced a decrease in the phase-transition enthalpy and a rise in the transformation temperature, even though no obvious martensite transformation was observed. This was suppressed due to the Fe element diffused from the substrate and was probably retarded by the mounting metallic compounds formed during annealing as well. The mechanical properties have also improved obviously; coatings annealed under 850 °C exhibited the highest microhardness of 839 HV, and the wear resistance of the coatings after annealing was enhanced with an 11% average wear mass loss reduction.

The influence of annealing treatment on the electrocatalytic oxidation performance of Cu46Zr44·5Al7.5Gd2 amorphous alloy

The influences of annealing on the microstructure and the performance of electrocatalytic oxidation of Cu46Zr44·5Al7.5Gd2 amorphous alloy were investigated by operating heat treatment in the vacuum annealing furnace. It is found that structural relaxation occurred in the internal structure of amorphous alloy after annealing treatment, which will cause a significant effect on the relative electrochemical performance. Choosing annealing temperature of 300 °C and holding time of 20 min, hydrofluoric acid corrosion treatment was applied on the relaxation structural stage ribbons. According to cyclic voltammetry and chronoamperometry curve graphs, it is found that it has a high oxidation peak as an electrode, whose corresponding electric potential is −0.11 V and current density is 0.0187 A cm−2. After reusing the experimental samples for 20 cycles, the electrocatalytic oxidation property on methyl alcohol is found to gradually decline and then stabilize. At 1-5 experiment cycles, the effect of electrocatalyst is relatively good, which proves that the sample ribbons can be recycled.

Magnetorheological fluid based on amorphous Fe-Si-B alloy magnetic particles

Magnetorheological fluids (MRFs) based on amorphous Fe-Si-B alloy magnetic particles were prepared. The influence of annealing treatment on stability and rheological property of MRFs was investigated. The saturation magnetization ( Ms) of amorphous Fe-Si-B particles after annealing at 550°C is 131.5 emu/g, which is higher than that of amorphous Fe-Si-B particles without annealing. Moreover, the stability of MRF with annealed amorphous Fe-Si-B particles is better than that of MRF without annealed amorphous Fe-Si-B particles. Stearic acid at 3 wt% was added to the MRF2 to enhance the fluid stability to greater than 90%. In addition, the rheological properties demonstrate that the prepared amorphous particle MRF shows relatively strong magnetic responsiveness, especially when the magnetic field strength reaches 365 kA/m. As the magnetic field intensified, the yield stress increased dramatically and followed the Herschel-Bulkley model.

Synthesis, thermodynamic analysis and magnetic study of novel ball- milled Co50Fe25Ta5Si5C15 glassy powders with high thermal stability

In this study, novel glassy Co–Fe–Ta–Si–C alloys were prepared by mechanical alloying, (MA) and the influence of annealing treatment and substitution of Fe for Co on glass-forming ability (GFA), thermal stability and magnetic properties were investigated. Quantitative X-ray diffraction (XRD) analysis by the Rietveld method showed that the new Co50Fe25Ta5Si5C15 powders have an enhanced glass formation rate, especially during the early milling stages compared to the Fe-free Co75Ta5Si5C15 alloy. In good agreement with the XRD measurements, the calculated PHSS thermodynamic parameter revealed that the GFA is notably increased for the new powder. Thermal analysis demonstrated a high thermal stability and a rather wide supercooled liquid region (SLR) of 51 K for the Co75Fe25Ta5Si5C15 glassy alloy. The milling process and subsequent annealing treatment remarkably improved the soft magnetic behavior of the Co75Fe25Ta5Si5C15 powder. The results indicated that the Co75Fe25Ta5Si5C15 glass exhibits a slightly higher coercivity (Hc) and a notably larger saturation magnetization (Ms) than the Co75Ta5Si5C15 alloy in the as-milled state. Furthermore, in the relaxed state, the new alloy possesses a markedly lower Hc of 0.96 kA/m and a higher Ms of 108 Am2/kg than Co75Ta5Si5C15 and large number of ssoft magnetic glasy powders prepared before. The influence of milling time and annealing temperature on the evolution of the magnetic properties were discussed in detail.

Excellent strengthening effect of L12 precipitates on the selective laser melting Al0.3CoCrFeNiCu high entropy alloy via annealing treatment

The influence of annealing treatment on the microstructure and mechanical properties of single phase structural Al0.3CoCrFeNiCu high entropy alloy (HEA) fabricated by selective laser melting (SLM) were investigated. The results indicated that the L12 precipitates were dispersed in matrix and also enriched at sub-grain boundaries of the SLM specimens annealed at 600 °C for 10 h. Besides, wetting transition was observed at the sub-grain boundary. Meanwhile, the microhardness and room compressive yield strength of this as-built HEA were dramatically enhanced from 255 HV and 419 MPa to 357 HV and 647 MPa after annealing treatment, respectively. Besides, the as-annealed HEA still possessed considerable ductility. Based on the microstructure analysis, the strength mechanism of as-annealed alloy was ascribed to the nano-sized L12 precipitates in sub-grains and also their enrichment at the sub-grain boundaries.

The microstructure and property of Al–Si alloy improved by the Sc-microalloying and Y2O3 nano-particles

ABSTRACT The effect of Sc-microalloying and Y2O3 nano-particles on the microstructure and mechanical properties of as-cast Al-5.5Si alloy is studied by means of optical microscopy, transmission electron microscopy, hardness test and tensile test. The influence of annealing treatment on the microstructure and properties of the Al-Si alloys is also investigated as well. The results show that the addition of Sc and Y2O3 nano-particles could significantly improve the mechanical property of the Al-Si alloy. The ultimate tensile strength and yield strength of Al-Si-Sc/Y2O3 alloy are improved by around 45 and 71%, respectively, when compared to that of the Al-Si alloy. The effect of the nanosized particles (precipitated and added) on strengthening and deformation of Al-Si alloy is analyzed and discussed in detail. The results of annealing treatment indicate that the change in mechanical property of the Al-Si-Sc alloy during annealing treatment is mainly associated with the precipitation of the secondary Si phase.

Influence of annealing treatment on the microstructure, mechanical performance and magnetic susceptibility of low magnetic Zr–1Mo parts manufactured via laser additive manufacturing

In recent years, a low magnetic and fully dense Zr–1Mo (wt%) part was successfully manufactured via the laser powder bed fusion (L-PBF) process, which shows the great potential as metallic biomaterials under the magnetic resonance imaging (MRI) environment. However, due to the high cooling rate after laser incident during the L-PBF process, the as-fabricated Zr–1Mo part consists of a non-equilibrium α′ phase, which contributed to high strength (UTS: 1107 MPa) but insufficient ductility (elongation: 4.3%) for biomedical applications. In order to enhance the mechanical performance of as-fabricated Zr–1Mo parts, various annealing processes that have been recognized as an efficient post-treatment to adjust the mechanical performance of additive manufactured products were executed. After the annealing process, acicular martensite α’ microstructure in as-fabricated Zr–1Mo parts changed to stress relieved/partial relieved acicular α microstructure, basketweave α + β microstructure, lamellar α + β microstructure or retain α+ lamellar α + β microstructure depending on different annealing conditions. In the meantime, elongation increased with increasing holding temperature and residence time, but the tensile strength exhibits a converse trend. The specimens annealed at 873 K, 803 K for 2 h and at 773 K for 8 h possessed UTS of 779 MPa, 964 MPa and 981 MPa as well as elongation of 14.3%, 11.0% and 9.6%, respectively. These annealing conditions could contributed to adequate strength and sufficient ductility, and should be the appropriate annealing conditions for Zr–1Mo parts produced by the L-PBF technology. By comparison with other conventional metallic biomaterials, annealed Zr–1Mo alloy could be applied for the medical devices under MRI environments. • Various annealing processes was executed for L-PBF-produced Zr–1Mo parts. • Correlation between microstructure and tensile properties of Zr–1Mo was understood. • Stress-relieved acicular structure contribute to high UTS and sufficient elongation. • 803 K-2 h shows comparable tensile properties to the several metallic biomaterials. • Excellent MRI compatibility was maintained after the annealing process.

Influence of Annealing treatment on Microstructure and Properties of Cold-drawn Al-3.0wt.%Mg Alloy

Influence of Annealing treatment on Microstructure and Properties of Cold-drawn Al-3.0wt.%Mg Alloy

Microstructure evolution and mechanical properties of Al0.4CoFeNiTi0.6 dual-phase high entropy alloy

The influence of annealing treatment on the microstructure evolution and mechanical properties of a new multi-principal component high entropy alloy (HEA) with dual-phase, Al0.4CoFeNiTi0.6, prepared by arc-melting, was investigated in detail. The as-cast alloy was composed of simple BCC and FCC phases which were further confirmed to be B2 and L12 structures. The yield strength (σ0.2), fracture strength and plastic strain of the as-cast alloy are 2085 MPa, 2136 MPa and 10.3%, respectively. Following annealing treatment, a large number of shortly rod-like phases are precipitated from the ordered BCC phase. The as-annealed alloy projects a decrease of ~33% in yield strength and a decrease of ~8% in fracture strength. However, the plastic strain is increased from 10.3 to 21%. The hardness increased from 467 HV to 548 HV, indicating that the alloy exhibits excellent temper-resistant softening properties.

Effect of annealing treatment on microstructures, mechanical properties and cavitation erosion performance of high velocity oxy-fuel sprayed NiCoCrAlYTa coating

The mechanical parts serving in the marine environment are up against the dual damage of corrosion and cavitation erosion, so the NiCoCrAlYTa coating with excellent corrosion resistance is successfully prepared by high velocity oxy-fuel (HVOF) sprayed technology to protect the equipment from deterioration. The chemical composition and mechanical properties as well as the microstructure evolution of the coating before and after annealing treatment are studied. At the same time, the influence of annealing treatment on the corrosion and cavitation erosion behaviors of the coating is investigated, as well. The NiCoCrAlYTa coating mainly contains γ-Ni, β-NiAl, and γ’-Ni3Al phases. During the deposition, the microcrystals or incomplete crystals generate in the interior of the coating because of the large temperature difference and impact force. Meanwhile, there is twin crystal structure in the as-spayed coating. After annealing treatment, the growth of grains and the segregation of reactive elements improve interface strength and inhibit the formation of micro-defects in the coating. The annealing temperature is of significance to the microstructure, mechanical properties, anti-corrosion and cavitation erosion resistance of the coating. This study provides a combined approach toward improving the corrosion and cavitation erosion resistance of NiCoCrAlYTa coatings.

Influence of melt spinning and annealing treatment on structures and hydrogen storage thermodynamic properties of La0.8Pr0.2MgNi3.6Co0.4 alloy

La0.8Pr0.2MgNi3.6Co0.4 alloys were prepared by induction melting, annealing and melt spinning techniques. The influences of annealing treatment and melt spinning on phase structure and hydrogen storage properties were systematically investigated. The results of X-ray diffraction determine that the as-cast and as-spun La0.8Pr0.2MgNi3.6Co0.4 alloys consist of LaMgNi4 and LaNi5 phases, while only LaMgNi4 phase is present in the as-annealed alloy. The scanning electron microscope images illustrate that the grain of the alloy is significantly refined by melt spinning technology. The gaseous hydrogen storage kinetic and thermodynamic properties were measured by using a Sievert’s apparatus at different temperatures. The maximum hydrogen storage capacity of the as-cast, as-spun and as-annealed La0.8Pr0.2MgNi3.6Co0.4 alloy is 1.699, 1.637 and 1.535 wt.% at 373 K and 3 MPa, respectively. The annealed alloy has flatter and wider pressure plateaus compared with the as-cast and as-spun alloys, which correspond to the hydrogen absorption and desorption process of LaMgNi4 and corresponding hydride. Furthermore, the enthalpy and entropy changes of LaMgNi4 during hydrogenation at different temperatures were calculated using Van’t Hoff methods.

The influence of annealing treatments on the microstructural and optical properties of a-SiCx:H films embedded with carbon nanodots

In order to obtain the carbon nanodots dispersed in the solid state films, carbon-rich amorphous hydrogenated silicon carbide (a-SiCx:H) films were prepared by PECVD method and were subsequently annealed at Argon protective environment for 30 min with different annealing temperatures (Ta). Raman spectra show that the amorphous carbon nanodots were formed within the a-SiCx:H films as Ta is equal to and higher than 600 °C. Meanwhile, the decomposition and transformation from sp3 C to sp2 C of the carbon nanodots can be inferred by the Raman spectra with increasing Ta. XPS analysis suggest that the near-surface oxidation of the films become strong as Ta > 600 °C which can be contributed to the chemical bond reconstruction and the formation of carbon nanodots within the films. The decrease of the optical band gap derived from the measured absorption spectra of the films can be attributed to the formation and graphitization of the carbon nanodots within the a-SiCx:H films. HRTEM measurements indicate that the enhancement of the areal density and the size reduction of the carbon nanodots take place within the a-SiCx:H films with increasing Ta. However, the dispersion of the carbon nanodots embedded in the a-SiCx:H films is still very bad compared with that of the CQDs dispersed in chemical solvents. PL measurements show that the PL signals may originate from the related defect states rather than the carbon nanodots within the a-SiCx:H films.

Modeling on Mechanical Properties of Zr-4 alloy Special Pipe during Annealing Treatments by ANN

In this paper, the influence of Annealing treatments and deformation on the mechanical properties of Zr-4 special pipe were modeled by artificial neural network (ANN). the optimal network architecture was considered to be 3-6-6 with momentum factor is 0.8 has been developed. The influence between mechanical properties of Zr-4 special pipe under different Annealing treatments and deformation has been proposed by using ANN model. It shows that the RMSE is 2.632, which shows good performance and results. The yield strength and tensile strength is slow dawn at first and then rise smoothly by reducing the second annealing temperature at room temperature. the elongation is going up and dropping with reducing the second annealing temperature at room temperature. The Part1 needed to cause recystallization.