Effect of heat treatment processes on microstructure and properties of P20 die steel

doi:10.13251/j.issn.0254-6051.2021.01.017

Abstract

Abstract: Poperties and microstructure of P20 steel with different heat treatment processes of “quenching+tempering”,“normalizing+tempering” and “hot rolling+tempering”,were compared and analyzed by means of Rockwell hardness and scanning electron microscopy (SEM).The results show that in despite of the difference of the hardness before tempering,the change trend of the three specimens were similar showing “slow down - a steep fall - and then slow down again”,and in the range of 580-600 ℃ all the three kinds of specimens showing the “steep fall” trend.The hardness at the “steep fall” is 37.12-32.31 HRC for quenching+tempering specimen,34.87-31.07 HRC for normalizing+tempering specimen and 35.00-31.63 HRC for hot rolling+tempering specimen,which is basically coincides with the range of 28-36 HRC required by GB/T 1299—2014.For the same tempering temperature,the hardness of “quenching+ tempering” specimen is higher than that of “hot rolling &tempering” specimen,while the hardness of “normalizing+tempering” specimen is lower than that of “hot rolling+tempering” specimen.

Key words: die steel, heat treatment, hardness, microstructure evolution

CLC Number:

TG156.5

Huang Biaocai, Ning Bo, Chen Yuye, Wu Huibin, Wei Yong, Zhan Guangcao, Yan Xiaomin. Effect of heat treatment processes on microstructure and properties of P20 die steel[J]. Heat Treatment of Metals, 2021, 46(1): 88-91.

References

[1] 赵新.P20钢预硬化热处理工艺的研究[J].热加工工艺,2009(14):135-136.
Zhao Xin.Study on pre-hardening process of P20 steel[J].Hot Working Technology,2009(14):135-136.
[2] 张兴锦,吴会亮,陈永南,等.P20塑料模具钢预硬化热处理工艺的研究[J].宽厚板,2015(4):38-41.
Zhang Xingjin,Wu Huiliang,Chen Yongnan,et al.Research of pre-hardening heat treatment process for P20 plastic mould steel[J].Wide and Heavy Plate,2015(4):38-41.
[3] 徐进,陈再枝,林慧国,等.模具材料应用手册[M].北京:机械工业出版社,2001.
[4] 宋义全,于健,刘宗昌,等.P20塑料模具钢的回火组织与硬度[J].包头钢铁学院学报,2003(1):42-45.
Song Yiquan,Yu Jian,Liu Zongchang,et al.Microstructure and hardness of plastic die steel P20[J].Journal of Baotou University of Iron and Steel Technology,2003(1):42-45.
[5] 丛文龙,于志军,孙海燕.冷却速度对大厚度P20塑料模具钢硬度的影响[J].大型铸锻件,2017(1):33-35.
Cong Wenlong,Yu Zhijun,Sun Haiyan.Influence of cooling speed on hardness of P20 plastic mold steel with large thickness[J].Heavy Casting and Forging,2017(1):33-35.
[6] 高阳.P20塑料模具钢的冶炼工艺实践[J].大型铸锻件,2018 (1):5-6.
Gao Yang.Smelting process and practice of P20 plastic mould steel[J].Heavy Casting and Forging,2018 (1):5-6.
[7] 李勇,左秀荣,陈蕴博,等.P20塑料模具钢淬火及回火组织性能的研究[J].热加工工艺,2010(6):126-129.
Li Yong,Zuo Xiurong,Chen Yunbo,et al.Research on microstructure and property of P20 plastic die steel after quenching and tempering[J].Hot Working Technology,2010(6):126-129.
[8] 李明,张逖.P20塑料模具钢低能耗热处理工艺的生产实践[J].现代冶金,2016,44(2):7-10.
[9] 李行,秦坤,任树洋,等.非调质预硬型塑料模具钢P20的开发[J].宽厚板,2017,23(6):41-43.
Li Xing,Qin Kun,Ren Shuyang,et al.Development of P20 non-quenching prehardened plastic die steel[J].Wide and Heavy Plate,2017,23(6):41-43.
[10] 罗毅,吴晓春.预硬型塑料模具钢的研究进展[J].金属热处理,2007,32(12):22-25.
Luo Yi,Wu Xiaochun.Research progress or prehardened plastic mould steel[J].Heat Treatment of Metals,2007,32(12):22-25.
[11] 郭海滨,左秀荣,张新理,等.P20塑料模具钢的回火工艺[J].金属热处理,2016,41(4):128-133.
Guo Haibin,Zuo Xiurong,Zhang Xinli,et al.Tempering process of P20 plastic die steel[J].Heat Treatment of Metals,2016,41(4):128-133.
[12] 李勇,雷文华,周毅.两相区热处理对P20钢组织与性能的影响[J].金属热处理,2016,41(1):175-178.
Li Yong,Lei Wenhua,Zhou Yi.Influence of two-phases region heat treatment on microstructure and mechanical properties of P20 steel[J].Heat Treatment of Metals,2016,41(1):175-178.
[13] 孙玮,崔风平.中厚板生产900问[M].北京:冶金工业出版社,2014:127-128.
[14] 朱志强,许玉宇,顾伟.钢分析化学与物理检测[M].北京:冶金工业出版社,2013:13.

[1]	Jia Changyuan, Huo Yuanming, He Tao, Huo Cunlong, Liu Keran. High temperature tensile deformation behavior and microstructure evolution law of 40CrNiMo steel [J]. Heat Treatment of Metals, 2022, 47(4): 69-74.
[2]	Liu Liyan, Bi Wenzhen, Wei Xicheng. Effect of Mn element on microstructure evolution of galvanized coating of hot stamping steel [J]. Heat Treatment of Metals, 2022, 47(4): 93-99.
[3]	Fu Xibin, Chen Zihao, Zhang Ke, Zhao Shiyu, Sun Xinjun, Zhu Zhenghai, Liang Xiaokai, Yong Qilong. Effect of quenching temperature on microstructure and mechanical properties of high Ti low alloy wear-resistant steel [J]. Heat Treatment of Metals, 2022, 47(4): 122-127.
[4]	Li Li, Zeng Yan, Wu Xiaochun. Heat treatment process optimization for 4Cr5Mo2VCo steel [J]. Heat Treatment of Metals, 2022, 47(4): 133-140.
[5]	Sun Kai, Chen Yan, Yang Shaobin. Effect of aging temperature on microstructure and hardness of laser selective melting TC21 titanium alloy [J]. Heat Treatment of Metals, 2022, 47(4): 155-158.
[6]	Zhang Jun, Zhao Sixin. Spheroidizing annealing process of 16MnCrS5 steel for cold forging gear [J]. Heat Treatment of Metals, 2022, 47(4): 185-188.
[7]	Wang Fangjun, Wang Dongzhe, Wan Hong, Shi Yao, Shen Tao. Effects of heat treatment and cold deformation on linear expansion coefficient of constant expansion alloy 4J32C [J]. Heat Treatment of Metals, 2022, 47(4): 199-203.
[8]	Wang Shaozhuo, Meng Han, Wang Fen, Fan Haiwei, Li Yan, Tang Chao. Heat treatment for improving mechanical properties of hypoxic TC4-LC and remelted TC4 alloys [J]. Heat Treatment of Metals, 2022, 47(4): 204-207.
[9]	Dai Jianke, Han Shun, Li Yong, Liu Xianmin, Wang Chunxu, Pang Xuedong, Li Jianxin. Microstructure and properties of C69 gear steel for aviation after high temperature carburizing [J]. Heat Treatment of Metals, 2022, 47(4): 219-225.
[10]	Su Yong, Wang Shuai, Wang Jixing, Yu Xingfu, Liu Hongxiu, Liu Jinling. Effect of compound chemical heat treatment on microstructure and hardness of G13Cr4Mo4Ni4V steel [J]. Heat Treatment of Metals, 2022, 47(4): 226-230.
[11]	Wang Jingyuan, Wu Songquan, Zhang Bohua, Xin Shewei, Yang Yi, Wang Hao, Huang Aijun. Effects of solution treatment and aging on microstructure and hardness of BT25y titanium alloy [J]. Heat Treatment of Metals, 2022, 47(3): 14-19.
[12]	Sun Jian, Huang Zhenyi, Li Jinghui, Wang Ping. Effect of solution treatment and aging on microstructure and hardness of Fe-Mn-Al-C light weight steel [J]. Heat Treatment of Metals, 2022, 47(3): 34-38.
[13]	Yang Chunmiao, Wang Shan, Wang Shuhui, Li Yanzhen, Liu Wenwen. Influence of pre-aging time on microstructure and properties of 7A85 aluminum alloy during RRA process [J]. Heat Treatment of Metals, 2022, 47(3): 44-47.
[14]	Fan Yang, Yang Minghua, Chen Kaimin, Sun Bingyan. Effect of PWHT on microstructure and mechanical properties of electron beam welded joints of 31CrMoV9 steel [J]. Heat Treatment of Metals, 2022, 47(3): 57-60.
[15]	Chen Shanyong, Wang Kuaishe, Qiao Ke, Wang Wen. Effect of alkali heat treatment on corrosion resistance of friction stir processed AZ31 magnesium alloy [J]. Heat Treatment of Metals, 2022, 47(3): 61-66.