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Effect of subcritical heat treatment on microstructure and properties of high chromium cast irons

Yuan Zhizhong, Liu Haiming, Ju Yulin, Chen Lu, Niu Zongran, Wang Zhiyuan, Cao Fuyang, Cheng Xiaonong

Heat Treatment of Metals 2024, 49 (10): 1-7. doi:10.13251/j.issn.0254-6051.2024.10.001

Abstract （244）

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Aiming at the problem of high energy consumption in conventional quenching and tempering process of high chromium cast irons, the subcritical heat treatment tests of three kinds of high chromium cast irons were carried out. Moreover, the effect of the process on the microstructure, hardness and surface wear resistance was studied. The results show that the microstructure of high chromium cast irons is primarily composed of retained austenite, M₇C₃ carbide, (Fe, Cr)₂₃C₆ carbide, Mo₂C carbide and pearlite when subjected to holding temperatures ranging from 500 ℃ to 650 ℃ for 1 h to 14 h. A peak value in hardness is observed for the three high chromium cast irons when holding at 550 ℃ to 600 ℃ for 6 h to 12 h, with the highest peak hardness being 57.4 HRC. The hardness is most significantly influenced by the Mo element. During the insulation process, the pearlite phase transformation of austenite is promoted by the precipitation of secondary carbides in high chromium cast irons. The effects of pearlite transformation strengthening and precipitation strengthening of secondary carbides gradually decrease with prolonged holding time. The eutectic high chromium cast iron with the highest carbon content exhibits the best wear resistance when holding at 600 ℃ for 8 h. It can be seen that the first step to improve the wear resistance of high chromium cast irons is to increase the amount of eutectic carbides, and then to add elements such as Mo to enhance the precipitation strengthening effect.

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Effect of cryogenic treatment on microstructure and mechanical properties of H13 steel

Di Yingnan, Ma Dangshen, Zhou Jian, Chi Hongxiao, Gu Jinbo

Heat Treatment of Metals 2024, 49 (10): 38-42. doi:10.13251/j.issn.0254-6051.2024.10.006

Abstract （240）

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Microstructure evolution and mechanical properties of the H13 steel during cryogenic treatment for different time (0-4 h) were studied. The phases and microstructure were analyzed by XRD and SEM, and the mechanical properties were characterized by hardness, impact and tensile tests. The experimental results show that the cryogenic treatment can refine martensite laths, promote the transformation of retained austenite to martensite and the precipitation of banded carbide. The increase of C content in martensite results in increasing in lattice constant and in lattice distortion effect, and a shift to the left in the XRD diffraction peak. With the prolongation of cryogenic treatment time, the strength and hardness of the steel show an upward trend, while the toughness and plasticity gradually decrease. Under the condition of maintaining the same hardness, the plasticity of the H13 steel after cryogenic treatment is comparable to that of the normal heat treatment, and its strength and toughness are improved.

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Heat treatment for toughening technology of cold working die steel SKD11

Yuan Zhizhong, Wang Mengfei, Zhang Bocheng, Duan Xubin, Li Biaomin, Yang Haifeng, Luo Rui, Cheng Xiaonong

Heat Treatment of Metals 2023, 48 (9): 1-7. doi:10.13251/j.issn.0254-6051.2023.09.001

Abstract （235）

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SKD11 steel plate after hot rolling and spheroidizing annealing was used. Two kinds of complex phase heat treatment processes, A-Q-A (Austempering-Quenching-Austempering) and Q-T-A (Quenching-Tempering-Austempering), as well asconventional Q-T(Quenching-Tempering) heat treatment process were carried out.The effect of heat treatment process on the microstructure, hardness and impact absorbed energy was studied. The results show that the microstructure of the specimens after A-Q-A and Q-T-A is the combination of lower bainite (LB) and martensite (M). The content of retained austenite is 13.2% and 18.6% for A-Q-A and Q-T-A, respectively. After A-Q-A, Q-T-A and conventional heat treatment Q-T, the hardness of the specimens is 58.5, 58.6 and 60.5 HRC and the impact absorbed energy is 31.3, 27.6 and 15 J, respectively. The excellent combination of strength and toughness of the SKD11 steel plate is realized by the duplex-phase heat treatments, which does a beneficial exploration in improving the toughness of the cold working die steel.

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Effect of vacuum low pressure carburizing on microstructure and properties of austenitic stainless steels 304 and 316L

Cheng Ru, Tian Yong, Song Chaowei, Wang Haojie

Heat Treatment of Metals 2022, 47 (9): 1-5. doi:10.13251/j.issn.0254-6051.2022.09.001

Abstract （230）

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Surface strengthening of 304 and 316L austenitic stainless steels was processed by using vacuum low pressure carburizing process. The microstructure, phase composition and microhardness distribution of the carburized layers were analyzed by means of optical microscope, scanning electron microscope, Thermo-Calc software, X-ray diffractometer and microhardness tester. The offsets of different diffraction peaks in the carburized layers and the changes in lattice parameters before and after carburizing of the tested steels were calculated. Combined with the effects of molybdenum on carburizing process of the austenitic stainless steels, the differences in the carburized layer thickness, surface hardness and mechanism of carbides precipitation after carburizing of 304 and 316L austenitic stainless steels were compared and studied. The results show that the carburized layers produced by 750 ℃ carburizing for 2.6 h are composed of expanded austenite and Cr₂₃C₆ phases, the austenite lattice constant has increased by 1.33% and 1.14% respectively for 304 and 316L stainless steels, and Cr₂₃C₆ is mainly precipitated in strip shape on the expanded austenite grain boundaries. The surface hardness of the 304 and 316L stainless steels after carburizing at 750 ℃ for 2.6 h is over 2 times higher than that of substrate.

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Effect of solution temperature on mechanical properties and corrosion resistance of super duplex stainless steel 2507

Gu Guochao, Li Ruifen, Xin Zhenmin, Xiang Lixin, Xu Wenhua, Lü Yupeng

Heat Treatment of Metals 2022, 47 (6): 1-6. doi:10.13251/j.issn.0254-6051.2022.06.001

Abstract （197）

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Effect of solution temperature on microstructure, mechanical properties and corrosion resistance of 2507 super duplex stainless steel was investigated by using optical microscope, scanning electron microscopy, XRD, tensile test and electrochemical analysis. The thermodynamic equilibrium phase diagram of the 2507 duplex stainless steel was calculated by Thermo-Calc thermodynamic software and compared with the test results. The results show that σ phase can be eliminated by solution treatment at temperatures higher than 1050 ℃. With the increase of solution temperature, the content of ferrite phase increases, the content of austenite phase decreases, and the volume fraction ratio of α/γ increases. The duplex stainless steel has better comprehensive mechanical properties after solution treatment at 1050-1100 ℃ for 30 min and water cooling, of which the yield strength, tensile strength and elongation are more than 600 MPa, 840 MPa and 35%, respectively. The duplex stainless steel can obtain better corrosion resistance after solution treatment at 1050 ℃ for 30 min.

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Intensive quenching and tempering of 40Cr steel

Yang Denggui, Zhu Xiaoshuo, Fu Yudong, Alinuer·Maimaiti

Heat Treatment of Metals 2023, 48 (2): 117-123. doi:10.13251/j.issn.0254-6051.2023.02.018

Abstract （195）

PDF （572KB）（62）

CaCl₂ aqueous solution was used as quenching medium to carry out intensive quenching process for the 40Cr steel, followed by high temperature tempering. The microstructure, mechanical properties and fracture morphologies were characterized by means of optical microscope, scanning electron microscope, hardness tester, impact and tensile tester, and compared with that of the oil quenching and tempering process. The results show that the fine and uniform tempered martensite can be obtained by intensive quenching with CaCl₂ quenching medium and high temperature tempering compared with oil quenching and tempering process. After intensive quenching and tempering, compared with conventional quenching and tempering process, the hardness is increased by 8%-18%, the strength is increased by 3%-5%, and the impact property is increased by 16%-30%, which can meet the requirements of higher service performance. The optimal quenching and tempering process for the 40Cr steel is austenitizing at 850 ℃ for 20 min, followed by intensive quenching with CaCl₂ quenching medium, and then tempering at 580 ℃ for 120 min plus air cooling.

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Effect of solution treatment on microstructure of carbide in K447A superalloy

Wu Wenjin, Li Xianghui, Li Xuechen, Chen Jingyang, Tang Xin

Heat Treatment of Metals 2022, 47 (6): 89-92. doi:10.13251/j.issn.0254-6051.2022.06.016

Abstract （193）

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Microstructure and precipitation behavior of carbides in K447A alloy under different solution treatments were analyzed by scanning electron microscopy(SEM). The results show that primary carbides in the as-cast K447A alloy are of the MC type, in the form of blocks, skeletons and Chinese characters, and are distributed between dendrites and grain boundaries. After heat treatment, primary MC carbides are broken, and a layer of γ' phase coating layer is formed on the surface. During heat treatment, the composition of the primary MC carbides changes, and the primary carbides such as TaC, TiC, and WC are decomposed, and HfC is least affected. After heat treatment, a large number of fine and dispersed granular secondary MC carbides dominated by HfC precipitate in the interdendritic and residual eutectic regions near the primary MC carbides. When solution-treated at 1185 ℃ for 2 h and aged at 870 ℃ for 20 h, the amount of secondary MC precipitation is the largest.

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Effect of solution treatment and aging on microstructure and hardness of TC11 titanium alloy

Zhu Ningyuan, Chen Shihao, Liao Qiang, Chen Qiuming, Lai Wenkun, Zuo Shoubin

Heat Treatment of Metals 2022, 47 (12): 62-66. doi:10.13251/j.issn.0254-6051.2022.12.010

Abstract （192）

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Effects of solution temperature and solution time on microstructure and microhardness of TC11 titanium alloy bar under the same aging treatment processes were studied. The results show that when the TC11 titanium alloy is solution treated below the phase transition point, the content of equiaxed primary α phase increases with the increase of solution temperature. When the solution temperature approaches the phase transition point, the content of equiaxed primary α phase decreases rapidly. When the solution temperature is 950 ℃, with the increase of solution time, the grain boundary α phase begins to grow, and the lamellar α phase turns into the mixed microstructure of bulk α phase and equiaxed α phase. When the solution time is fixed, the hardness of the TC11 titanium alloy decreases first and then tends to be stable with the increase of solution temperature. The hardness reaches the maximum value when solution temperature is 950 ℃ and solution time is 120 min.

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Effect of secondary forging deformation on microstructure and impact properties of Cr-Mo-V die steel after spheroidal annealing

Xia Yunfeng, Ma Danning, Yang Qiang, Zhou Zhongcheng, Wang Jiaoqi

Heat Treatment of Metals 2024, 49 (10): 99-104. doi:10.13251/j.issn.0254-6051.2024.10.016

Abstract （192）

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Effect of secondary forging deformation on microstructure, precipitation and impact properties of Cr-Mo-V die steel was studied by means of metallographic microscope, scanning electron microscope, high resolution transmission electron microscope and impact testing machine. The results show that compared with conventional upsetting and drawing deformation, the microstructure and network carbides of the die steel after spheroidizing annealing under secondary radial forging and secondary upsetting and drawing deformation processes are significantly optimized, the impact absorbed energy are improved by 12% and 58%, respectively, and the precipitated carbides increases in quantity and is dispersed.

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Microstructure and thermal processing map of Inconel 600 alloy

Zhou Yusen, Cheng Xiaonong, Luo Rui, Gao Pei, Liu Yu, Yuan Zhizhong

Heat Treatment of Metals 2022, 47 (10): 107-112. doi:10.13251/j.issn.0254-6051.2022.10.017

Abstract （190）

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Thermal processing map of Inconel 600 alloy was obtained through thermal compression experiment by using Gleeble-3500 testing machine, and the microstructure corresponding to different zones of the thermal processing map was studied. Finally, the actual hot extrusion production was carried out by using the thermal processing window given by the thermal processing map. The results show that when the strain is 0.6, the thermal processing window is generally stable in the low strain rate region of 0.01-0.1 s^-1 and the high strain rate 10 s^-1 at 1150-1200 ℃. The actually produced pipe has a good macro morphology, and the microstructure is basically equiaxed recrystallized grains with twins, which are refined comparing with that of as-annealed alloy.

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Effect of solution treatment temperature and time on corrosion resistance of high nitrogen stainless steel

Zhang Cunshuai, Liu Jimeng, Li Hao, Zhao Dingguo, Wang Shuhuan, Ni Guolong

Heat Treatment of Metals 2022, 47 (8): 141-147. doi:10.13251/j.issn.0254-6051.2022.08.023

Abstract （181）

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High nitrogen nickel-free austenitic stainless steel with 0.54%N was prepared by vacuum induction furnace+electroslag remelting furnace under 0.08 MPa. After hot rolling, the tested steel was solution treated at 800, 900, 1000, 1100 and 1200 ℃ for different time, respectively. The microstructure and corrosion resistance of the tested steel were studied with different solution treatment processes, in which the corrosion resistance was studied in 3.5% NaCl solution by potentiodynamic polarization curve, and the mass loss ratio and corrosion rate were calculated after soaking in 6% FeCl₃ solution for 8 days. The results show that solution treatment has a great influence on microstructure and corrosion resistance of the high nitrogen stainless steel. The tested steel after solution treatment at 1000 ℃ and 1100 ℃ has a single austenite structure. The precipitation phase Cr₂N exists in the microstructure of the tested steel without heat treatment and in that solution treated at 800 ℃ and 900 ℃. In the tested steel solution treated at 1200 ℃, the ferrite structure is precipitated from the austenite. The tested steel heated at 1100 ℃ for 1 h has the best corrosion resistance, and the corrosion rate is only 1.35×10^-5 g·cm^-2·h^-1. While the corrosion resistance of the tested steel heated at 800 ℃ for 3 h is the worst, the corrosion rate is as high as 8.18×10^-4 g·cm^-2·h^-1. The corrosion resistance of 316L stainless steel is somewhere in between, and the corrosion rate is 1.24×10^-4 g·cm^-2·h^-1.

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Effect of austenitization temperature on microstructure and mechanical properties of 40CrMnSi2Mo steel under air cooling

Yu Linran, Liu Geng, Yang Zhuoyue, Su Jie, Ning Jing, Ding Yali

Heat Treatment of Metals 2024, 49 (12): 1-8. doi:10.13251/j.issn.0254-6051.2024.12.001

Abstract （179）

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Effect of austenitization temperature (875-975 ℃) on the microstructure and mechanical properties of the novel Cr-Mn-Si series high strength medium carbon low alloy 40CrMnSi2Mo steel under air cooling condition was studied by means of optical microscope (OM), scanning electron microscope (SEM), transmission electron microscope (TEM) and laser scanning confocal microscope (LSCM). The results show that when austenitized at 875 ℃ and 900 ℃, the microstructure is dominated by martensite with a small amount of the undissolved precipitates (NbC). The prior austenite grains are fine and stable. The tensile strength is 1997 MPa and 2003 MPa, the elongation is 11.0% and 12.0%, and the fracture toughness is 70.3 MPa·m^1/2 and 73.6 MPa·m^1/2, respectively. When austenitized at 975 ℃, the solubility of NbC increases and the pinning effect decreases. The growth of austenite grain size decreases the thermal stability so that the coarse bainite/martensite multiphase is obtained under air cooling. The tensile strength is 1980 MPa, the elongation is 10.5%, and the fracture toughness is only 77.6 MPa·m^1/2. The effect of the austenite grain refinement on the strength and toughness of the 40CrMnSi2Mo steel is not obvious. The fine bainite/martensite multiphase can be obtained after austenitizing at 950 ℃. The mechanical properties achieve an excellent combination, with the tensile strength of 2040 MPa, the elongation of 12% and the fracture toughness of 86.6 MPa·m^1/2.

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Effects of solution and aging treatments on mechanical properties and microstructure of Al-Cu-Mn-Er cast alloy

Wu Yang, Huang Hui, Shi Wei, Wen Shengping, Wu Xiaolan, Rong Li, Wei Wu

Heat Treatment of Metals 2022, 47 (6): 7-12. doi:10.13251/j.issn.0254-6051.2022.06.002

Abstract （175）

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Effects of different solution and aging treatments on microstructure and mechanical properties of Al-Cu-Mn-Er alloy were studied by optical microscope, scanning electron microscope, XRD, DSC test, hardness test and tensile test. The results show that the optimal process of solution and aging treatments of the as-cast alloy is solution treating at 540 ℃ for 12 h and aging at 185 ℃ for 6 h, under which there is no overheating or "overburning" phenomena, the solute atoms are fully diffused, and a large amount of residual phases generated during the casting process are redissolved into the matrix. Meanwhile, the alloy has the highest hardness value of 142.28 HV0.1, tensile strength of 370.37 MPa, yield strength of 300.34 MPa, and elongation of 6.50%.

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Effect of final cooling temperature on microstructure and properties of Q345R steel

Zhang Deyong, Feng Yangfeng, Li Weijuan, Li Wei, Xu Jiyong, Qi Minxiang

Heat Treatment of Metals 2022, 47 (5): 230-233. doi:10.13251/j.issn.0254-6051.2022.05.040

Abstract （172）

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Final cooling test was carried out on the pressure vessel steel Q345R, and the effect of final cooling temperature on mechanical properties and microstructure of the as-rolled and normalized steel plate was studied. The results show that the mechanical properties of the as-rolled and normalized Q345R steel at different final cooling temperatures meet the standard requirements, but when directy air cooled after rolling, the performance margin is small. When the final cooling temperature is 650 ℃, the mechanical properties are relatively better. With the increase of final cooling temperature, the yield strength, tensile strength, and impact property of the steel plate have a downward trend, and the microstructure gradually becomes coarser. The microstructure of the as-rolled and normalized specimens are all typical ferrite+pearlite, and after normalization of the steel plate, the yield strength and tensile strength are significantly lower than that of the hot-rolled steel plate, while the impact property is significantly improved, and the microstructure becomes finer.

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Effect of quenching process on microstructure and properties of martensitic stainless steel 6Cr13

Li Zhaoguo, Pan Jixiang, Ji Xianbin, Wei Haixia, Wang Ke

Heat Treatment of Metals 2022, 47 (5): 226-229. doi:10.13251/j.issn.0254-6051.2022.05.039

Abstract （167）

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Effect of quenching at 950-1150 ℃ with different cooling methods on microstructure and mechanical properties of martensitic stainless steel 6Cr13 was studied. The results show that with the increase of quenching temperature, the content of residual carbides decreases gradually, then at above 1050 ℃, the carbide dissolution rate increases and the grains begin to grow rapidly, and the content of residual austenite increases gradually, by which the hardness reaches the maximum at 1050 ℃ and then begins to decrease, and such decrease becomes the most obvious at 1150 ℃. The water-cooled hardness of the steel is higher than that air cooled at 950 ℃, but when air-cooled at above 950 ℃, the hardness is higher than that of water-cooled. Air cooling at 1050 ℃ can obtain a higher quenching hardness, a lower retained austenite content, and a carbide content of 8%, with better wear resistance and higher sharpness.

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Effect of spheroidization annealing process on austenite grain size of 16MnCr5 steel for carburizing

Zheng Xiaowei, Lin Zaiyong, Zhang Jianfeng, Jin Tao

Heat Treatment of Metals 2023, 48 (5): 283-286. doi:10.13251/j.issn.0254-6051.2023.05.045

Abstract （167）

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In order to study the effect of spheroidizing annealing on austenite grain size of 16MnCr5 steel hot rolled wire rods during the process of modification, hot-rolled wire rod specimen and specimens isothermally spheroidizing annealed at 700, 720, 740, 760 and 780 ℃, respectively, for 5 h were subjected to water quenching at 940 ± 5 ℃ for 1 h. The austenite grain size of the specimens was measured and compared. The results show that the “double high” processes (heating temperature of 1200-1250 ℃, finishing rolling temperature of 950-980 ℃) and rapid cooling between 800-600 ℃ (air cooling, cooling rate ≥ 10 ℃/s) are used in the rolling process to ensure that aluminum and nitrogen atoms are in a solid solution state. During the heat treatment process before austenite grain detection, AlN is uniformly and finely precipitated, resulting in fine and uniform austenite grains in the 16MnCr5 steel. When spheroidizing annealed at 700 and 720 ℃, AlN particles are uniformly and finely precipitated. Although Ostwald aging and growth occur, the AlN particles are still smaller than the critical radius, and the austenite grains are still fine and uniform. With the further increase of spheroidizing annealing temperature, the second phase particles undergo Ostwald aging and growth. The second phase particles in local areas exceed the critical radius, and local austenite grains grow abnormally, resulting in mixed grains. In practical production, in order to obtain uniform and fine austenite grains, as well as good spheroidized microstructure and mechanical properties, 16MnCr5 steel is spheroidizing annealed at 720 ℃. Through the above controlled rolling process and spheroidizing annealing process, the austenitic grain size of 16MnCr5 steel can reach 7.5 grade to 7 grade, meeting the requirements of austenitic grain size ≥ 5 grade and without mixed grains.

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Effect of quenching process on hardened depth and mechanical properties of 42CrMo steel cutter hub

Jiang Ying, Du Shuiming, Huang Qiaomei, Shen Zida, You Fei

Heat Treatment of Metals 2023, 48 (9): 88-91. doi:10.13251/j.issn.0254-6051.2023.09.014

Abstract （160）

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42CrMo steel cutter cub was quenched by using a multi-purpose furnace at different quenching temperatures, different quenching media and carbon potentials. The influence of various factors on mechanical properties and depth of hardened layer of the cutter cub was studied through the inspection of mechanical properties, microstructure and hardness. The results show that with the increase of quenching medium cooling rate, the tensile strength of the cutter cub quenched at 850-890 ℃ shows a trend of overall increase. When the quenching temperature is 850 ℃, the tensile properties of the cutter cub is the best when the quenching medium D is used, and the depth of quenched layer reaches 6.0 mm. When the quenching temperature is 870 ℃, after using C medium, the depth of quenched layer meets the customer's requirements. When the carbon potential is 0.6%, with the increase of quenching temperature, the depth of the quenched layer first increases and then decreases, the tensile strength decreases, and the yield strength and elongation increase.

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Effect of solution treatment on microstructure transformation and element diffusion of Fe-Cr-Ni-Al alloy

Zhou Qiyun, Shi Zengmin, Xie Hao, Dai Lei

Heat Treatment of Metals 2022, 47 (5): 98-104. doi:10.13251/j.issn.0254-6051.2022.05.016

Abstract （159）

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Diffusion of elements and phase transformation of the Fe-Cr-Ni-Al alloy during solution treatment process were studied by means of OM, SEM and other methods, and a JMAK model of γ phase transformation was established by DSC data at different cooling rates. The results show that the matrix phase at room temperature of the as-cast Fe-Cr-Ni-Al alloy is γ phase and δ phase. After solution treatment at 1150 ℃, the content of the γ phase in the alloy increases, and the content of the δ phase decreases. The phase change of δ→γ occurs in the heating stage, and the phase change of γ→δ occurs in the isothermal soaking stage. Through the solution treatment, δ phase and γ phase evolve into a more obvious Cr-rich phase and Ni-rich phase, the difference of Cr and Ni elements between σ phases which located in different positions increases, and the component segregation between σ phases and their matrix decreases gradually. It can be proved by the JMAK model of austenite phase transition that the greater the cooling rate, the lower the starting temperature of the γ phase transition, and the larger the temperature interval of the transition, the greater the energy change caused by the reaction.

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Effect of solution treatment on microstructure and low temperature impact properties of 022Cr22Ni5Mo3N duplex stainless steel

Cui Liyun, Liu Qingtao, Luo Rui, Qian Xigen, Ding Hengnan, Sun Xi, Zhao Xiaotao, Liu Heng, Cheng Xiaonong

Heat Treatment of Metals 2024, 49 (10): 18-24. doi:10.13251/j.issn.0254-6051.2024.10.003

Abstract （155）

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Solution treatment for as-forged 022Cr22Ni5Mo3N duplex stainless steel was carried out, and the effects of solution temperature (1000-1100 ℃) and time (1 h and 2 h) on the microstructure and -46 ℃ low temperature impact properties were studied. The results show that with the increase of solution temperature, the austenite content of the 022Cr22Ni5Mo3N stainless steel decreases, the phase boundary of austenite tends to be smooth and the number of needle-type and island austenite in ferrite decreases gradually. The low temperature impact properties increase first and then decrease with the increase of solution temperature. When the solution temperature is 1050 ℃, the low temperature impact absorbed energy of the 022Cr22Ni5Mo3N stainless steel is higher, which is about 260 J. The solution treatment can change the austenite phase morphology and adjust the phase content. Serrated phase boundaries(below 1050 ℃) and lower austenite phase content(above 1050 ℃) promote the brittle fracture of dual-phase steels at low temperatures, which is the main reason for the reduction of low-temperature toughness.

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Effect of annealing process on grain size and texture intensity of non-oriented silicon steel

Wang Haijun, Niu Yuhao, Qiao Jialong, Ling Haitao, Qiu Shengtao

Heat Treatment of Metals 2023, 48 (12): 44-55. doi:10.13251/j.issn.0254-6051.2023.12.007

Abstract （151）

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Annealing processes of non-oriented silicon steel are described, and the researches on the effects of annealing temperature, annealing time, heating rate and annealing atmosphere on grain size and texture intensity of non-oriented silicon steel in recent twenty years are reviewed. In addition, the differences of microstructure and texture evolution of the cold-rolled sheet before and after annealing are compared and analyzed. Finally, the evolution characteristics of grains and textures during annealing of the non-oriented silicon steel are summarized.

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