摘要
利用L78淬火膨胀仪对一种高碳低合金耐磨钢进行900℃加热后以不同速度冷却的淬火试验,并用光学显微镜观察淬火试验钢的微观组织,用450SVD数显维氏硬度计测量硬度。结果表明,当淬火冷却速度小于0.4℃/s时,试验钢的组织为少量铁素体+珠光体,硬度值为254~313 HV5;冷却速度为0.4℃/s时,组织为全珠光体,硬度值为317 HV5;冷却速度为0.5~1℃/s时,组织为珠光体+贝氏体+马氏体+残留奥氏体,硬度值为435~726 HV5;冷却速度为2~3℃/s时,组织为贝氏体+马氏体+残留奥氏体,硬度值为726~753 HV5;当冷却速度达到4℃/s时,组织为马氏体+残留奥氏体,硬度为784 HV5;继续增大冷速至150℃/s时,组织无明显变化,硬度值变化较小,为810~825 HV5;当冷速达到180℃/s时,硬度值下降到785 HV5,组织仍然为马氏体+残留奥氏体,但残留奥氏体含量增多。
Tests of quenching at 900 ℃ with different cooling rates were carried out for a high carbon low alloy wear-resistant steel by using L78 dilatometer. The microstructure of the quenched steel was observed by metallographic microscope, and the hardness was measured by 450SVD digital Vickers hardness tester. The results show that when the cooling rate is less than 0.4 ℃/s, the microstructure of the tested steel is pearlite plus a small amount of ferrite, and the hardness value is 254-313 HV5. When the cooling rate is 0.4 ℃/s, the microstructure is full pearlite and the hardness value is 317 HV5. When the cooling rate is 0.5-1 ℃/s, the microstructure is composed of pearlite, bainite, martensite and retained austenite, and the hardness value is 435-726 HV5. When the cooling rate is 2-3 ℃/s, the microstructure is bainite, martensite and retained austenite, and the hardness value is 726-753 HV5. When the cooling rate reaches 4 ℃/s, the microstructure is martensite and retained austenite, and the hardness is 784 HV5. When the cooling rate further increases to 150 ℃/s, the microstructure has no obvious change, and the hardness value changes little, which is 810-825 HV5. When the cooling rate reaches 180 ℃/s, the hardness value drops to 785 HV5, while the microstructure is still martensite and retained austenite, but the amount of the retained austenite is increased.
作者
王权
高思远
魏文强
朱辉
Wang Quan;Gao Siyuan;Wei Wenqiang;Zhu Hui(Inner Mongolia Zhongtian Hongyuan Rare Earth New Material Co.,Ltd.,Baotou Inner Mongolia O14017,China;School of Materials and Metallurgy,Inner Mongolia University of Science and Technology,Baotou Inner Mongolia 014010,China)
出处
《金属热处理》
CAS
CSCD
北大核心
2024年第12期107-110,共4页
Heat Treatment of Metals
关键词
高碳低合金耐磨钢
淬火
冷却速度
显微组织
硬度
high carbon low alloy wear-resistant steel
quenching
cooling rate
microstructure
hardness
