摘要
通过热模拟试验得到55SiCrV钢的CCT曲线和奥氏体晶粒长大曲线,确定了淬火温度选择范围;利用双因子正交试验,研究了热处理参数对其力学性能及组织的影响。结果表明:在850~930℃加热温度范围内,Cr、V元素形成难溶碳化物,阻碍晶粒长大;随着温度的提高,55SiCrV钢奥氏体晶粒尺寸基本不变,晶粒度达到10级;加热温度930℃以上时,原子扩散能力增大,且难溶碳化物逐渐溶解,奥氏体晶粒度逐渐粗化。在870~930℃淬火温度范围内,随温度提高,55SiCrV钢抗拉强度先升高后下降;随回火温度提高,强度逐渐降低,塑性提高。900℃淬火+410℃回火工艺下,55SiCrV钢组织为针状铁素体与M3C碳化物组成的细小回火屈氏体,具有较好的疲劳性能和抗弹减性能。
CCT curves and austenite grain growth curve of 55SiCrV steel were obtained by thermal simulation,and selection range of quenching temperature was determined.The effects of heat treatment parameters on mechanical properties and metallographic structure of the material were studied by two-factor orthogonal test.The results show that in the heating temperature range of 850-930℃,Cr and V elements form insoluble carbides hindering grain growth;with the increase of the heating temperature,the austenite grain size of 55SiCrV steel is basically unchanged and reaches grade 10.When the heating temperature is above 930℃,the atomic diffusion capacity increases,the insoluble carbides dissolve gradually,and the austenite grain size gradually coarsens.Within the quenching temperature range of 870-930℃,the tensile strength of 55SiCrV steel increases first and then decreases as the temperature increases.As the tempering temperature increases,the strength decreases gradually and the plasticity increases.Under 900℃quenching+410℃tempering process,55SiCrV steel microstructure is fine tempered troostite composed of acicular ferrite and M3C carbide,which has good fatigue performance and anti-ballistic performance.
作者
姜婷
汪开忠
于同仁
龚梦强
张晓瑞
Jiang Ting;Wang Kaizhong;Yu Tongren;Gong Mengqiang;Zhang Xiaorui(Maanshan Iron & Steel Co.,Ltd.,Maanshan Anhui 243000,China)
出处
《金属热处理》
CAS
CSCD
北大核心
2019年第10期96-99,共4页
Heat Treatment of Metals
关键词
55SiCrV钢
热处理
力学性能
组织
55SiCrV steel
heat treatment
mechanical properties
microstructure
