15CrMo钢管件热处理工艺试验

15CrMo steel pipe fitting heat treatment process experiment

15CrMo管材在抽检过程中多次出现延伸率不达标,抗拉强度、屈服强度偏高的现象。对不合格的管材进行热处理并取样分析,根据试验结果进行管件成型,最终确定管件的热处理工艺试验方案:(1)正火温度为(940±10)℃,保温60 min,然后喷雾冷却;(2)回火温度为(690±10)℃,保温120 min,然后空冷。热处理后做拉伸试验,15CrMo管件的抗拉强度为505～510 MPa,屈服强度为310～335 MPa,延伸率≥29%,管件成型温度为850～900℃。

The phenomenon of unqualified elongation, higher tensile strength and yield strength of 15CrMo pipe fitting oc- curred repeatedly in process of inspection. Unqualified pipe fitting was sampling analyzed after heat treatment, pipe forming was done according to experiment result, the heat treatment process experiment solution of pipe fitting was decided finally, （1） normalizing temperature （940 ± 10）℃, holding time 60 min, then spray cooling. （2）tempering temperature （690 ± 10）℃, holding time 120 min, then air cooling. Tensile test was done after heat treatment, 15CrMo pipe fitting tensile strength is 505 - 510 MPa, yield strength is 3 I0 -335 MPa, elongation rate is no less than 29%, pipe fitting mold temper- ature is 850 ~ 900 ~C.