Effect Of Annealing Treatment Research Articles

Effect of annealing and heat-moisture pretreatment on the quality of 3D-printed wheat starch gels

This paper examines the effects of annealing treatment (ANN) and heat-moisture treatment (HMT) on the physicochemical and structural properties of wheat starch used for 3D food printing. Printing performance, molecular weight (Mw), amylopectin branch chain length distribution, pasting properties, rheology, fourier transform infrared (FT-IR) spectroscopy, texture and scanning electron microscopy (SEM) were used to evaluate the quality of printed products. Compared to untreated wheat starch, HMT improved the accuracy of 3D printing, stacking height of printed samples, and prolonged storage time of printed sample with softer texture. Conversely, ANN decreased printing performance, made sample edges rougher, reduced the stacking height of printed samples, and significantly increased sample hardness in storage. These effects are consistent with changes that these treatments made to the Mw of starch: compared to native starch and ANN, HMT increased the Mw of amylose and significantly decreased average Mw. In turn, this change decreased viscosity and G' of the starch gel, enabling smoother extrusion and better printing lines. In conclusion, HMT can improve 3D printing performance of wheat starch, increasing printing height and accuracy, which provides a simple and effective method to improve 3D printing effect using starch.

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 annealing treatment on response characteristics of Pd-Ni alloy based hydrogen sensor

The response rate and anti-interference performance are crucial to the detect performance for Pd-based hydrogen sensors. In this study, a resistance- type palladium-nickel (Pd90Ni10) thin film hydrogen sensors were prepared by the ion beam sputtering method. Sensors with an optimized Pd90Ni10 thickness (90 nm) which showed the fastest response for hydrogen were selected to study the effect of annealing treatment to the response rate and anti-interference performance. Four groups of samples were annealed at 250°C, 300°C, 350°C, and 400°C in air atmosphere for 4 hours, respectively. The impact of annealing treatment on base resistance stability and hydrogen response characteristics were studied. SEM, EDS and XRD analysis were carried out to reveal the relationship between response characteristics and microstructures. Results show that annealing treatment was beneficial to the base resistance stability and response rate. Samples annealed at 350°C showed the best base resistance stability and response rate. Furthermore, the difference of response rate ∆ was improved for the annealing treatment, indicating the improvement of the hydrogen sensor regarding the anti-interference effect to other gases. Meanwhile, a new mechanism including mutli-factors of Pd-Ni alloy about the anti-interference of oxygen was proposed based on our study. Besides, the sensors with the optimized fabrication process were tested in mixed standard gas with various hydrogen concentrations. This work provides an outstanding guidance to fabricate of hydrogen sensors of high response rate and anti-interference performance.

The effect of annealing treatment on thermoelectric properties of nanostructured Bi0.5Sb1.5Te3 thin films fabricated by ball milling and thermal evaporation

The effect of annealing treatment on thermoelectric properties of nanostructured Bi0.5Sb1.5Te3 thin films fabricated by ball milling and thermal evaporation

Effect of annealing treatment on the mechanical properties of spiked-shell aerographite particles

The spiked-shell microparticles of aerographite exhibit excellent flexibility owing to their unique shell structures consisting of radially aligned hollow carbon nanorods. However, their flexibility is likely transitory, and fatigue damages related to imperfections in the crystallinity of their graphitic layers are observed upon cyclic deformation. In this study, aerographite microparticles were heat treated to examine the effects of annealing on their crystallinity and mechanical behaviors. Experimental results showed that the crystallinity of the particles was improved by annealing above 1600 °C; however, excess annealing at 2000 °C caused severe changes in the shell morphology, leading to a lack of flexibility. Single-particle-level compressive test results showed that the particles annealed at 1600 °C performed significantly better in terms of mechanical behaviors by reducing the probability of fracture due to large crack propagation. These particles also exhibited excellent flexibilities in their stress–strain relationships even after 100-times cycle tests. These findings suggest that annealing treatment at 1600 °C is an effective option to improve the mechanical properties of aerographite particles.

Effect of annealing treatments on the mechanical behaviour of UHTCMCs prepared by mild polymer infiltration and pyrolysis

Cf/ZrB2–SiC composites were produced by water-based slurry impregnation followed by six cycles of polymer infiltration and pyrolysis at 1000 °C. Despite the mild temperature of pyrolysis, the flexural strength of this composite showed values in excess of 500 MPa even at elevated temperature, up to 1400 °C. The abrupt decay of strength at 1500 °C stimulated the need to investigate the effect of additional thermal treatments enabling the crystallization of the amorphous polymer derived SiC(O). Annealing treatments, carried out between 1400 °C and 1900 °C, led to evident microstructural changes that in turn affected the flexural strength measured both at room temperature and at 1500 °C. The microstructural evolution was carefully analysed and 1400 °C was identified as the best trade-off between temperature of the annealing treatment and mechanical performance. After annealing at 1400 °C, the strength of the composite at room temperature decreased from the initial 500 MPa for untreated samples to 300 MPa due to the creation of new porosity, but this strength value was then maintained up to 87% at 1500 °C. Annealing at higher temperatures were detrimental for microstructure and strength.

Effect of annealing treatment on microstructural and mechanical properties of a hot-forged FeCrCuMn2Ni2 high-entropy alloy

The present study prepared an as-cast ingot of a FeCrCuMn2Ni2 high-entropy alloy using vacuum induction melting process, followed by hot forging at 650–750 °C. The samples were then annealed at temperatures between 600 and 1100 °C for 2 h, and were characterized in terms of their microstructural features and mechanical properties. No phase transformation was observed for the hot-forged and annealed samples. Compared to the as-cast state, the hot-forged sample exhibited higher compressive yield strength and hardness, but lower compressive strain. This behavior can be due to the precipitation of hard σ-phase with an average size of 0.55 µm during hot forging. It was further observed that the precipitates dissolved, when the temperature exceeded 1000 °C, resulting in discontinuous static recrystallization with an average grain size of 15.9 µm. Annealing between 600 and 800 °C decreased the compressive yield strength and compressive strain, which could be attributed to σ-precipitates morphological change and their growth up to an average size of 1.34 µm. On the other hand, when the annealing temperature increased above 800 °C, the compressive yield strength decreased and compressive strain increased. This behavior was attributed to the dissolution of a large amount of σ-precipitates, growth of the residual σ-precipitates, and softening of the alloy. Findings further revealed a decrease in the hardening capacity value of annealed samples in the range of 600–800 °C, resulting from the formation of σ-precipitates. In contrast, the hardening capacity value of the alloy increased with the annealing temperature, due to the grains size increase at higher temperatures.

Effect of Annealing Treatment on the Recrystallization of a Single Crystal Superalloy

Recrystallization often occurs in the production of aero engine turbine blades of single crystal superalloys. It is believed that annealing treatment can reduce the recrystallization tendency, as some of the casting residual stress is released. To evaluate the annealing effect on recrystallization, tensile test is carried out in present study for as-cast specimens of a second generation single crystal superalloy to induce stress. Two different annealing treatments are applied to the prestrained specimens, followed by the solution treatment at 1300°C for 2h. In order to compare the effect of the annealing treatments, the specimens are investigated by x-ray Laue diffraction technique and metallographic observation. According to the comparison, the more effective annealing treatment is recommended.

Effect of annealing treatment on the physicochemical properties and enzymatic hydrolysis of different types of starch

Annealing treatment on the physicochemical properties and hydrolysis of maize, potato and pea starch were investigated in present study. Results indicated that annealing treatment did not change the morphology of the starch. However, the relative crystallinity of maize and potato starch showed a peak trend as the annealing time extended, while pea starch showed a lower relative crystallinity. Besides, all the annealed starch showed a decrease in peak viscosity and an increase in pasting time. Little difference in the rapidly digestive starch (RDS) and resistant starch (RS) contents of annealed maize starch and pea starch were observed after annealing, while annealed potato starch (72 h) showed an increased RS content (23.37 ± 5.36 %) and a decreased RDS content (52.60 ± 6.14 %), respectively. The obtained results may provide a better understanding of the physicochemical properties and enzymatic hydrolysis of annealed starch with different semi crystalline type.

Effects of annealing treatments on forming performance of zirconium alloys

The effects of annealing treatments (ATs) on the microstructure of Zr−Sn−Nb alloy strips were studied. Based on the characteristics of strips for nuclear fuel assemblies, punching experiments were carried out and the formability of zirconium alloy strips was quantitatively evaluated. The results indicate that the proportions of small-angle grain boundaries of the zirconium alloy under conditions of annealing treatment at 580 °C (AT I) and annealing treatment at 620 °C (AT II) are 14.3% and 23.2%, respectively, while that of the as-received material is 12.4%. And the forming limit margin fields of the zirconium alloy under AT I can reach 0.43%, while the values of the as-received material and the AT II are −0.35% and −2.8%, respectively. The annealing process affects the evolution process of the strip recrystallization texture and the grain size. Moreover, the total texture and pole density are closely related to the degree of anisotropy of the strip. Besides, the small-angle grain boundary affects the strain path and crack expansion of the necking unit during the strip punching process, while the grain size affects the hardening exponent of the material.

Effect of annealing treatment on the microstructure and current carrying tribological properties of in-situ formed TiO2−x coating prepared by plasma spraying

Titanium suboxide (TiO2−x) of Magnéli phases was in-situ formed by using supersonic plasma spraying with the agglomerated TiO2 powders. The effect of annealing treatment on phase constitution, microstructure, mechanical, electrical and tribological properties of the as-sprayed TiO2−x coating was analyzed. The results showed that the phase constitution and microstructure of the annealed TiO2−x coatings transformed with the annealing temperatures, which greatly affected the mechanical properties and electrical conductivity. Compared to dry friction, the friction coefficients of the coatings declined under the action of electric current. Owing to the increase in the roughness and intensification of the abrasive properties on the worn surfaces, the wear loss of the coatings increased notably under current-carrying condition.

Significant evolutions of microstructure and mechanical properties of Al0.3CoCrFeNiTix high-entropy alloys under annealing treatment

The effect of annealing treatment on microstructure and mechanical properties of Al0.3CoCrFeNiTix high entropy alloys were investigated. The results indicated that addition of Ti in as-cast alloys caused the formation of L12, Laves, γ and σ phases to increase the hardness and strength of the alloys. The microstructure remained stable below annealing at 700 °C. However, the (Fe, Cr)-rich phase was found in the interdendritic (ID) structure. Simultaneously, annealing at 700 °C increased the volume fraction of L12, γ and σ phases and decreased the volume fraction of FCC and Laves phases. The (Al, Ni, Ti)-rich rod-shaped precipitated (RSP) phase was found in the FCC matrix after annealing at 800 °C. The hardness and yield strength showed a significant enhancement after annealing at 700–800 °C. The coarsening phenomenon of (Fe, Cr)-rich and RSP phases could be observed after annealing at 900–1000 °C. Simultaneously, annealing at 900–1000 °C caused the further decrease in the volume fraction of FCC and Laves, causing the decrease in yield strength and to improve plasticity of the alloys. The main strengthening mechanisms of as-cast and annealed Tix alloys were discussed, confirming that the precipitation strengthening mechanism was the main strengthening mechanism.

Effect of annealing treatment on microstructure and tensile properties of Ti-48Al-2Cr-5Nb alloy fabricated by laser additive manufacturing

Using laser additive manufacturing (LAM), a Ti-48Al-2Cr-5Nb alloy was fabricated and studied systematically for its microstructure, phase composition, texture, and tensile properties. The results indicate that both the microstructure of as-deposited and annealed alloys consists of phases Ti3Al (α2) and TiAl (γ). When the annealing temperature was increased, the microstructure changed significantly and a greater amount of lamellar α2 phase precipitated between the lamellae. Meanwhile, the thickness of γ lamellar at the edges of lamellar clusters increased. In comparison with the annealed alloy, the secondary annealed alloy demonstrated a significant coarsening of the lamellar γ phase. Increasing the annealing temperature gradually increased the texture strength of the γ (111) orientation. At room temperature and high temperature, the as-deposited alloy had a higher tensile strength than the annealed alloy. Ti-48Al-2Cr-5Nb alloy samples secondary annealed at 1260 °C/1h/FC exhibited the highest elongations at room temperature, 750 °C, and 850 °C, with values of 1.6%, 3.8%, and 4.8%, respectively. As compared to the as-deposited alloy, the elongation increased by 1.15, 1.36, and 1.07 times, respectively.

Effects of Annealing Treatment on Corrosion Resistance of Arc Sprayed Aluminum Coating

Effects of Annealing Treatment on Corrosion Resistance of Arc Sprayed Aluminum Coating

Effect of annealing treatment on microstructure evolution and deformation behavior of 304 L stainless steel made by laser powder bed fusion

This paper focuses on the microstructural evolution of 304 L austenitic stainless steel (SS) manufactured by laser powder bed fusion (LPBF) after stress-relieving annealing (650 °C) and solution annealing (1050 °C). Multiple advanced characterizations were adopted to disclose the microstructural characteristics and investigate the annealing-driven dislocation migration process. At 650 °C, the dislocation density of cellular walls decreased slightly, associated with a slight decrease of strength. At 1050 °C, the dislocations of cellular walls migrated to more energetically favorable regions, forming subgrain boundaries with higher dislocation density and resulting in a strength-ductility trade-off. The temperature of 1050 °C could slightly increase the recrystallization volume fraction and induce the coalescence of multi-oriented fine-grained tribes into single-oriented grains. The nano-scale characterization indicated that the as-built samples and annealed samples at 650 °C contained the square lattice distortion networks composed of orthogonal strain ripples. However, after annealing at 1050 °C, only unidirectional strain ripples in square lattice distortion networks were retained due to unidirectional dislocation migration. Direct experimental results were provided that the local misorientation ranges of cellular interior, cellular walls, and newly formed subgrain boundaries were <0.2°, 0.2°-0.5°, and 0.5°-2°, respectively. After tensile deformation, interacting deformation twins occurred in <111> and 〈101〉 oriented grains of as-built and annealed specimens at 650 °C, while the twins occurred in all oriented grains of annealed specimens at 1050 °C due to the disappearance of cellular substructure and the increase of tensile elongation. This work yields new insights into misorientation across the cellular walls, dislocation migration process during annealing, strengthening mechanisms, and work hardening behaviors, which can be used to design and optimize future annealing routines for LPBF materials.

Effects of Annealing Treatment on Microstructure and Tensile Properties of Ti-48Al-2Cr-2Nb-5Ta Alloy by Laser Additive Manufacturing

Effects of Annealing Treatment on Microstructure and Tensile Properties of Ti-48Al-2Cr-2Nb-5Ta Alloy by Laser Additive Manufacturing

Effect of annealing treatment on microstructure, mechanical property and anti-corrosion behavior of X2CrNi12 ferritic stainless steel

The effect of annealing temperature on the microstructure, mechanical property and anti-corrosion behavior of the X2CrNi12 ferritic stainless steel were systematically investigated. The results demonstrate that a large amount of (Fe, Cr)23C6 precipitated at the ferrite grain boundaries after annealing below 740 °C. The precipitation of the (Fe, Cr)23C6 was prevented with the increase of annealing temperature, and the martensite content gradually increased, which improved the tensile strength, yield strength, and hardness of the steels, while the elongation was decreased. The best comprehensive mechanical properties can be obtained at the annealing temperature of 850 °C and 950 °C. The ductile-dimple fracture is the primary fracture mode for the steels. The corrosion rates of the stainless steels first decreased and then increased with the increase of annealing temperature. The 770 °C-annealed steel has the best anti-corrosion ability. The corresponding corrosion mechanism can be attributed to the pitting corrosion induced by the (Fe, Cr)23C6 and martensite. Moreover, the precipitation of (Fe, Cr)23C6 could consume the Cr in the matrix and prevent the formation of passive film on the surface. And the phase transformation stress in the martensite can accelerate the local corrosion of the steel matrix.

YSZ/LSM Composite Cathode Deposited by Solution Precursor Plasma Spraying

In this paper, solution precursor plasma spraying (SPPS) was employed to prepare a porous YSZ/LSM composite cathode for solid oxide fuel cell (SOFC). The surface morphology and microstructure of the composite cathode deposits were characterized using SEM. The effect of annealing treatment on SPPS YSZ/LSM microstructure was examined. The results showed that the as-sprayed YSZ/LSM deposits presented a porous aggregate with a size range of 10–60 μm when the alcohol was used as the solvent and the spraying distance was 60 mm. The porous aggregate was found to be composed mainly of small particles ranging from 0.2–2 μm, the YSZ/LSM composite cathode showed a finely porous microstructure with grain sizes from micrometers to sub-micrometers. A further annealing treatment at 1050 °C for 2 h in air resulted in a continuous microstructure porous coating with a perovskite phase. The polarization test results demonstrated that the minimum polarizations were 1.26 and 0.083 Ω·cm2 for the composite cathode at 800 and 1000 °C, respectively.

Annealing Time Effect on Intermetallic Compounds of Hot Dip Galvanizing Coating

The use of zinc coatings deposited onto steel is one of the most important commercial processing techniques employed to protect steel components exposed to severe corrosive environments. Our objective is to improve the coated galvanizing steel used as irrigation tube in the agriculture field. After the best mechanical and chemical preparation, the substrates of this steel were galvanized by immersion in a molten zinc bath heated at 450°C during 15 min. the coated steel substrates underwent an annealing treatment in classical furnace heated at 350 °C for various holding times. This research work is to investigate the time effect of annealing treatment on intermetallic compounds of coatings obtained by hot dip galvanizing steel. For this purpose, several characterization means are used to evaluate the change effected by the annealing time on the phases of galvanizing coating. The kinetic growth of each layer relates the thickness to the annealing time by a simple power law. The treatment of annealing at temperature of 350 °C and holding time of 150 min can changed the structural and mechanical properties of coating phases. The gamma and delta layers presented the hard inner layers became relatively soft phases which would not lead to cracking and detachment of the coating.

Effects of annealing treatment on tribological behaviour of tungsten‐doped diamond‐like carbon film under lubrication (Part 1): Chemical composition, mechanical properties and tribological behaviour under base oil

AbstractTungsten‐doped diamond‐like carbon (W‐DLC) films were prepared by magnetron sputtering, followed by annealing in the temperature range of 100–500°C. The effects of the annealing treatment on the chemical compositions, mechanical properties and tribological behaviours of annealed W‐DLC films with a base oil were tested by scanning electron microscopy, atomic force microscopy, Raman spectroscopy, x‐ray diffraction and nanoindenter tests. The results indicated that increasing the annealing temperature led to a decrease in the thicknesses and hardness values of the W‐DLC films due to the graphitization and oxidation of the film surfaces. However, the structures of the W‐DLC films annealed at 500°C were destroyed. Under poly‐alpha olefin lubrication, when the annealing temperature was lower than 300°C, the tribological properties of the W‐DLC films were stable. This occurred because the graphitization of the sample surface was conducive to the removal of abrasive particles.