调质态40CrNi2Mo钢的低温力学性能  

Mechanical properties of quenched and tempered 40CrNi2Mo steel at low temperatures

作　　者：张伟强[1,2] 郭金[2] 

机构地区：[1]沈阳理工大学材料科学与工程学院,辽宁沈阳110159 [2]辽宁工程技术大学力学与工程学院,辽宁阜新123000

出　　处：《煤炭学报》2012年第1期167-171,共5页Journal of China Coal Society

摘　　要：为了确定调质态40CrNi2Mo钢在不同应变速率下的低温力学性能及其相互关系,采用静拉伸、系列冲击及分离式霍普金森压杆试验对40CrNi2Mo钢低温力学性能进行了研究。结果表明,随温度降低,40CrNi2Mo钢静拉伸强度提高,而塑性下降;其韧脆转变温度出现在-40～-51℃。在高速应变条件下,钢的屈服强度和加工硬化指数均随着试验温度的降低而降低;而压缩率主要随应变速率的增大而增加。高速应变产生的绝热剪切效应降低了钢在低温状态下的强度,也促进了冲击韧性的急剧下降。Quasi-static tension,Charpy impact and SHPB（Split Hopkinson Pressure Bar） methods were employed to study the mechanical properties of 40CrNi2Mo steel which was quenched and tempered at 650 ℃ so that the effects of both low temperature and strain rate were understood.The results show that low temperature results in an increase in static tension strength of the steel but a decrease in ductility.Ductile to brittle transition occurs at-40^-51 ℃ indicated by impact test.At high stain rates（2 500~4 000 s-1） both the yield strength and the strain-hardening index are reduced as temperature decreases,whereas the compression ratio is increased with the strain rate increasing.The effect of adiabatic shear occurs during deformation of the steel at high strain rates,inducing a tendency of decrease in low-temperature strength and abrupt reduce in the impact toughness.

关 键 词：40CRNI2MO钢 分离式霍普金森压杆 低温 力学性能 

分 类 号：TG142.1[一般工业技术—材料科学与工程]