摘要
对含0.389%C、0.807%Cr、1.715%Ni和0.237%Mo(质量分数)的40NiCrMo7钢进行了850℃油淬、590℃回火。热处理后,对钢在250~550℃进行了拉伸试验和在400~550℃以160~500 MPa的应力进行了低周次蠕变试验。研究了钢的线膨胀量、平均线膨胀系数、高温拉伸性能和低周次高温蠕变性能随温度的变化。结果表明:随着温度从20℃升高至700℃,钢的线膨胀量先增大后减小再增大;随着温度从20℃开始升高,钢的平均线膨胀系数先增大后减小,在20~700℃钢的平均线膨胀系数最大;随着温度从250℃升高至350℃,钢的抗拉强度和屈服强度均下降,但塑性显示出相反的变化趋势;温度和应力对调质态40NiCrMo7钢的高温蠕变行为有显著影响,以相同应力在不同温度进行蠕变试验时,温度越高,蠕变越充分,而在相同温度以不同应力蠕变试验时,应力越大,蠕变越充分。
40NiCrMo7 steel containing 0.389%C,0.807%Cr,1.715%Ni and 0.237%Mo by mass was oil quenched from 850℃then tempered at 590℃.After heat treating,the steel was subjected to tensile tests which were performed at temperatures ranging from 250 to 550℃and to low cycle creep tests which were performed at temperatures ranging from 400 to 550℃at stresses ranging from 160 to 500 MPa.The linear expansion,average linear expansion coefficient,high temperature tensile properties and low cycle high temperature creep properties as a function of temperatures for the steel were investigated.The results showed that(a)as the temperatures increased from 20 to 700℃,the linear expansion of the steel increased at first and then decreased,and increased again;(b)as the temperatures increased from 20℃,the average linear expansion coefficient of the steel increased at first and then decreased,and reached the maximum at the temperatures ranging from 20 to 700℃;(c)as the temperature increased from 250 to 350℃,both the tensile strength and the yield strength of the steel decreased,but the plasticity showed the opposite trend;(d)the temperature and the stress had significant effects on the high temperature creep behavior of the quenched-and-tempered 40NiCrMo7 steel,during the creep test at the same stress at different temperature,the higher the temperature,the more full the creep was,whereas during creep test at the same temperature at different stresses,the greater the stress,the more full the creep was.
作者
陈炜
于晃
王思倩
牛丹
包翠敏
马国军
邹鹏
薛吉
CHEN Wei;YU Huang;WANG Siqian;NIU Dan;BAO Cuimin;MA Guojun;ZOU Peng;XUE Ji(Shenyang Turbo Machinery Co.,Ltd.,Shenyang 110869,Liaoning China;Dalian Turbine Machinery Technology Development Co.,Ltd.,Dalian 116023,Liaoning China;State Key Laboratory of Structural Analysis for Industrial Equipment,Dalian Universityof Technology,Dalian 116024,Liaoning China)
出处
《热处理》
CAS
2023年第3期9-11,17,共4页
Heat Treatment
关键词
调质
40NiCrMo7钢
线膨胀
高温拉伸性能
蠕变性能
quenching-and-tempering
40NiCrMo7 steel
linear expansion
high temperature tensile property
creep property
