热处理时间对CHE608HR低合金钢焊条熔敷金属力学性能的影响

Effect of heat treatment holding time on mechanical properties of deposited metal of low-alloy steel electrode CHE608HR for nuclear equipment

针对核级蒸发器支承用低合金钢焊条CHE608HR,采用固定热处理保温温度为620℃、改变热处理保温时间的方法,借助金相显微镜研究热处理保温时间对其焊缝金属力学性能及组织的影响。结果表明,熔敷金属的拉伸强度随着热处理保温时间的增加而降低,低温冲击性能随着热处理保温时间的增加先升高后降低。热处理保温时间为1～24 h时,可获得综合力学性能良好的熔敷金属。

Low-alloy steel electrode CHE608HR is used for support of nuclear steam generator. Adopting PWHT temperature of 620 ℃ with different PWHT holding times,the influence of postweld heat treatment (PWHT) holding time on the mechanical properties and microstructure of weld metal is studied by metallographic microscope. The results show that as PWHT holding time increases,the tensile strength of deposited metal reduces and impact property at low temperature rises at first and then decreases. Wtih the PWHT holding time of 1~24 h,good comprehensive mechanical properties of deposited metal can be obtained.