中南大学学报（自然科学版）2017，Vol.48Issue(3)：585-591,7.DOI:10.11817/j.issn.1672-7207.2017.03.005
大型筒节升梯式临界区正火热处理工艺
Lift type critical region normalizing heat treatment process of heavy cylinder
摘要
Abstract
The lift type critical region normalizing (LTCRN) heat treatment process (HTP) was put forward based on the fact the center part of heavy cylinder was prone to mixed grain and crystal grain structure, long period of heat treatment, large energy consumption after the isotherm type austenite region normalizing (ITARN) process. The microstructure and mechanical properties were verified by the proposed HTP method. The results show that the LTCRN on eliminating mixed grain is better than that with ITARN method, and the average grain size is 31 μm after the heat treatment. Also, part of cementite precipitation on the grain boundary plays a pining and strengthening role of the grain boundary and the cementite spheroidization and homogenization inside the grain is also more effective. Besides, the yield strength, tensile strength and the-30℃ charpy impact energy of the heavy cylinder material are 655 MPa, 729 MPa and 162 J respectively after the LTCRN HTP, with significantly more plastic ridge and the comprehensive mechanical properties are the same as the ITARN method. Compared with the ITARN, the holding time of LTCRN can be shortened by 30% and the normalizing temperature is also decreased, which greatly reduces the energy consumption.关键词
大型筒节/升梯式临界区正火/热处理/力学性能Key words
heavy cylinder/lift type critical region normalizing/heat treatment process/mechanical properties分类
矿业与冶金引用本文复制引用
孙建亮,张永振,彭艳,戚向东,韩辉..大型筒节升梯式临界区正火热处理工艺[J].中南大学学报（自然科学版）,2017,48(3):585-591,7.基金项目
中国博士后科学基金资助项目(2016M590211) （2016M590211）
河北省高等学校青年拔尖人才计划项目(BJ2014055) (Project (2016M590211) supported by the Postdoctoral Science Foundation of China （BJ2014055）
Project(BJ2014055) supported by the Youth Talent Program of Colleges in Hebei Province, China) （BJ2014055）
