Cr-W-Mo-V高碳中合金钢在αγ相变过程的碳化物转变及形貌

Transformation and Morphology of Carbides in Cr-W-Mo-V High Carbon Medium-alloy Steels during αγ Transforming Process

研究表明,Cr-W-Mo-V高碳中合金钢加热至αγ温度区附近,M23C6和M3C会逐渐溶解于基体中,缓冷过程逐渐析出M23C6、M3C,并在αγ温度区发生M23C6M6C转变,而球状VC则变化不大,其碳化物超细化主要南溶解、形核的转变过程所引起的。碳化物细化及不均匀程度依赖于碳化物类型及其比例,因此,合理的成分设计是常规锻轧和热处理工艺下获得超细碳化物高碳中合金钢的关键。

The investigation shows that M23C6 and M3C in Cr-W-Mo-V high carbon medium-alloy steels gradually dissolve into the matrix during heat process at about αγ temperature, and gradually precipitate again from the matrix during low cooling process. Moreover, transformation of M23C6M6C takes place and change of VC particle is lesser at a-bout αγ temperature. The process of dissolving and precipitating of the carbides particles lead to ultra-fine distribution. The degree of fine and asymmetry of carbides depend on the types of carbide and their partition. Thus, it is important that the alloy composition design is carried out properly for medium-alloy high carbon steel with multiple types of ultra-fine carbides under normal forging and annealing conditions.