V-Nb微合金化重载齿轮钢的组织和力学性能

Microstructure and mechanical properties of V-Nb microalloyed steel for heavy-duty gear

研究了Cr-Ni-Mo系重载齿轮钢经V-Nb微合金化处理前后的组织及力学性能。结果表明:经过V-Nb微合金化处理后,钢的奥氏体晶粒得到显著细化,在渗碳温度范围内10h保温时不会发生奥氏体晶粒的异常长大;伴随着晶粒的细化,冲击吸收功得到了提高;晶粒细化也使该钢渗碳层的组织和性能得到了改善。

The microstructure and mechanical properties of Cr-Ni-Mo case hardening steel with or without V-Nb microalloying for heavy-duty gear were investigated. Results show that V-Nb microalloying is effective to promote the properties of the Cr-Ni-Mo steel by refining the austenite grain size significantly, which resulted in an increase of its impact energy. The V-Nb microalloyed steel could not show abnormal coarsening of austenite grain when it is held in the temperature range of carburization for 10 h, and the mechanical properties of the carburizing case are also improved.