The evolution of carbides in the tempering process of semi-high speed steel cold rolls with nitrogen addition

作     者：WU Qiong SUN Dale YAO Lisong LIU Changsheng 

作者机构：School of Materials ＆ Metallurgy Northeastern University Shenyang 110004 China Equipment Division Baosteel Research Institute Baoshan Iron ＆ Steel Co. Ltd. Shanghai 201900 China 

出 版 物：《Baosteel Technical Research》 (宝钢技术研究（英文版）)

年 卷 期：2009年第3卷第2期

页      面：42-45页

学科分类：080503[工学-材料加工工程] 08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 0802[工学-机械工程] 080201[工学-机械制造及其自动化] 

基　　金：supported by the Baosteel Group Corporation Project (R05DSES220) 

主　　题：carbide evolution precipitation sequence secondary hardening characteristic EDX spectra 

摘      要：This study analyzes the evolution of carbides in the tempering process of a newly developed semi-high speed steel cold forged roll with nitrogen addition using a transmission electron microscope （TEM） equipped with an energy dispersive X-ray （EDX）. The precipitation sequence of the carbides was identified in the entire tempering process and it can be expressed as M3C→M3C ＋ M （C, N）Ⅱ→M（ C, N）Ⅱ → M7C3Ⅱ ＋ M23 C6. The secondary hardening in the tempering process was mainly due to the dispersed precipitation of fine M（ C, N）n particles. The dissolution of M3 C tempered at high temperatures induced the precipitation and coarsening of M7 C31/ and M23 C6.