The thermal process for hardening the nitrocarburized layers of a low-carbon steel

被引：2

作者：

Chen, Wanglin ^{[1
,5
]}

Huang, Yonghao ^{[1
]}

Xiao, Hui ^{[2
]}

Meng, Xianna ^{[3
]}

Li, Zhe ^{[1
]}

Chen, Zhaoxiang ^{[1
]}

Hong, Yue ^{[4
]}

Wu, Cuilan ^{[5
]}

机构：

[1] Guangdong Univ Technol, Sch Electromech Engn, Guangdong Prov Key Lab Minimally Invas Surg & Mfg, Guangzhou 510006, Peoples R China

[2] Foshan Univ, Sch Mechatron Engn & Automat, Foshan 528225, Peoples R China

[3] South China Univ Technol, Sch Mech & Automot Engn, Guangzhou 510006, Peoples R China

[4] Guangdong Acad Sci, Inst New Mat, Guangzhou 510651, Peoples R China

[5] Hunan Univ, Coll Mat Sci & Engn, Changsha 410082, Hunan, Peoples R China

来源：

SCRIPTA MATERIALIA | 2022年 / 210卷

基金：

中国国家自然科学基金;

关键词：

Nitrocarburizing; Undesirable microstructure; Austenitizing; Isothermal transformation; Bainitic structure; MICROSTRUCTURE; IRON;

D O I：

10.1016/j.scriptamat.2021.114467

中图分类号：

TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

Undesirable microstructures, with thin or uneven compound layers, pores, pearlitic structures, vein-like nitrides, etc., are detrimental to mechanical and tribological properties of nitrocarburized components. Here, we report a novel heat process in which a thicker nanobainitic layer, consisting of gamma' lamellas and alpha-Fe laths with high-density alpha ''-phase GP-zones, is obtained by heating the undesirable nitrocarburized layer at 700 degrees C (austenitizing) followed by isothermal aging at 225 degrees C for 14 h. The total phase- transformation sequences of this process are described as: epsilon + gamma' -> gamma-N/C -> gamma' + alpha-Fe + GP-zones. The thicker nanobainitic layer exhibits much higher hardness, load-bearing capacity, fracture toughness and wear resistance as compared to the nitrocarburized layer, and corresponding mechanisms for strengthening and toughening are shown. (C) 2021 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

引用

页数：4

共 14 条

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