C含量对高氮奥氏体不锈钢18Mn18CrN析出行为的影响  

Effects of C content on precipitation behavior of high-nitrogen austenitic stainless steel 18Mn18CrN

作　　者：陈雨来[1] 房菲 李静媛[1] 王一德[1] 

机构地区：[1]北京科技大学材料科学与工程学院,北京100083 [2]中国核电工程有限公司,北京100840

出　　处：《材料热处理学报》2015年第9期94-102,共9页Transactions of Materials and Heat Treatment

基　　金：国家'十二五'科技支撑计划项目(2012BAE04B02);国家自然科学基金(51174026)

摘　　要：研究碳（C）含量为0.05%~0.77%时对18Mn18CrN高氮奥氏体不锈钢750~850℃时效析出行为的影响。结果表明,C含量未改变实验钢中析出方式和析出相类别,Cr2N析出相首先沿晶界以颗粒形貌析出,而后以片层状向晶内生长。随着时效时间的增加,片层状析出相体积分数及片层间隙增加,元素的扩散是控制其长大的主要因素。增加C含量可降低Cr2N相析出孕育时间,增加Cr2N相体积分数,降低Cr2N相扩散激活能,其中QD（A1）=157.63kJ·mol-1;QD（A3）=32.92kJ·mol-1。随C、N含量增加,实验钢中Cr2N相体积分数呈线性趋势增加,但其增加程度更敏感于N含量的变化。The effects of carbon content from 0. 05% to 0. 77% on the precipitation behavior of 18Mn18 CrN high nitrogen austenitic stainless steels aging at 750-850 ℃ were investigated. It is found that carbon contents can not change the precipitating behavior and kinds of precipitation in the tested steels. The granular Cr2N phases precipitate along grain boundaries,and then grow from grain boundaries into grain in the way of lamellar structure. The volume fraction and lamellar spacing of Cr2N phase increase as the aging time increases. The growth of Cr2N phase is mainly controlled by the diffusion of elements. With the increase of C content,the incubation time of Cr2N phase decreases,the volume fraction of Cr2N phase increases and the diffusion activation energy of Cr2N phase decreases,such as QD（ A1） =157. 63 k J·mol- 1; QD（ A3） = 32. 92 k J·mol- 1. The volume fraction of the precipitates increases linearly with the change of C and N content,and the increase of the volume fraction of the precipitates is more sensitive to the change of N content.

关 键 词：高氮奥氏体不锈钢 C含量 N含量 析出相 扩散激活能 

分 类 号：TG142.7[一般工业技术—材料科学与工程]