60Si2Mn冷拔珠光体钢丝快速球化退火工艺

通过对60Si2Mn冷拔珠光体钢丝进行快速球化退火处理,即将其加热到810 ℃奥氏体化,保温1.5 min后随炉冷却至500 ℃出炉空冷,研究了其力学性能、球化效果、球化时间和快速球化的机理,并与普通球化退火及等温球化退火这两种常用球化退火工艺进行了对比。结果表明,与两种常用球化退火工艺相比,快速球化退火显著缩短了退火时间,且球化效果更好,其屈服强度、抗拉强度、伸长率、断面收缩率分别为620 MPa、745 MPa、21%和66.7%。球化时间的缩短主要是因为冷拔变形使钢中的位错密度和畸变能增加,促使片层状珠光体能够在加热过程中快速溶断,并促进渗碳体组织的球化。

Rapid spheroidizing annealing process of 60 Si2 Mn cold drawn pearlite steel wire

By austenitizing at 810℃for 1.5 min,furnace cooling to 500℃and then air cooling,a rapid spheroidizing annealing process was carried out for 60Si2Mn cold drawn pearlite steel wire,then the mechanical properties,spheroidizing effect,spheroidizing time and rapid spheroidizing mechanism were studied and compared with that of normal spheroidizing annealing and isothermal spheroidizing annealing processes.The results show that compared with the two common spheroidizing annealing process,the rapid spheroidizing annealing process can significantly shorten the spheroidizing time,and with better spheroidizing effect.The yield strength,tensile strength,elongation and reduction of area of the rapid spheroidizing annealed steel are 620 MPa,745 MPa,21%and 66.7%,respectively.The shortening of spheroidizing time is mainly due to the increase of dislocation density and distortion energy in the steel caused by cold drawing deformation,which enables the lamellar pearlite to change rapidly into disconnected parts by dissolving in the heating process,and promotes the spheroidization of cementite.