摘要
采用DIL805A型淬火变形膨胀仪,利用膨胀法结合金相-硬度法,绘制了40CrMnSiB钢的连续冷却转变曲线(CCT曲线),研究了冷却速率对组织和硬度的影响规律。结果表明:在试验条件下,40CrMnSiB钢相变温度A_(c1)为770℃,A_(c3)为823℃,M_(s)为322℃,M_(f)为176℃;随冷却速度增加,组织由软相铁素体+珠光体变为贝氏体和马氏体,显微硬度也逐渐提高。40CrMnSiB钢淬透性较高,当冷速为2℃/s时,开始发生贝氏体和马氏体转变;冷速为10℃/s时,组织为全马氏体。CCT曲线的测定为该钢种的生产实践和热处理工艺制定提供了参考依据。
The continuous cooling transition curve(CCT curve)of 40CrMnSiB steel was drawn by DIL805A quenching deformation dilatometer and expansion method combined with metallographic hardness method.The effect of cooling rate on microstructure and hardness was studied.The results show that the phase transition temperatures of 40CrMnSiB are as follows:A_(c1) is 770℃,A_(c3) is 823℃,M_(s) is 322℃,M_(f) is 176℃.With the increase of cooling rate,the microstructure changes from soft ferrite+pearlite to bainite and martensite,and the microhardness increases gradually.40CrMnSiB has a high steel hardenability,which start to transform to bainite and martensite at 2℃/s cooling speed and full bainite at 10℃/s.The CCT curve provides reference basis to the production practice and heat treatment process of this kind of steel.
作者
张雲飞
赵英利
樊明强
袁书强
陈炯
赵楠
宋月
Zhang Yunfei;Zhao Yingli;Fan Mingqiang;Yuan Shuqiang;Chen Jiong;Zhao Nan;Song Yue(HBIS Group Teehnology Research Institute,Shijiazhuang 050023,Hebei;Ningbo Branch of China Ordnance Research Institute,Ningbo 315103,Zhejiang)
出处
《河北冶金》
2022年第4期37-40,共4页
Hebei Metallurgy
