采用不同等温退火工艺对M2高速钢盘条进行了退火处理,研究了加热温度、保温时间和等温转变时间等工艺参数对其显微组织和力学性能的影响,在此基础上优化了其等温退火工艺.结果表明:加热温度过高和保温时间过长会使一次碳化物颗粒长大粗化,降低盘条的塑性;而等温转变时间过短不利于珠光体的形成,同样使盘条塑性不高;M2高速钢盘条比较合理的退火工艺为880 ℃加热2 h,炉冷至760 ℃等温5 h,可得到退火索氏体中弥散分布着细小球状一次碳化物颗粒的组织,使高速钢盘条具有良好的塑性.

The effect of annealing process parameters including heating temperature,holding time and isothermal transformation on microstructure and mechanical properties of M2 high speed steel wires processed by different isothermal annealing processes was investigated.The process was optimized on this basis.The results show that excessive high temperature and long time could cause the coarsening of primary carbides,reducing the plasticity.Excesssive short isothermal transformation time went against the forming of pearlite,and made the plasticity decreaesed.The appropriate annealing process of M2 wires was heating at 880 ℃ for 2 h and then furnace-cooled to 760 ℃ for 5 h.Fine and spherical primary carbides were formed in annealed sorbite after annealing with those parameters which cause the wires obtaining good plasticity.