图 1所示齿轮轴是透平压缩机中的关键零件 ,按其服役条件 ,采用 34ＣｒＮｉ3Ｍｏ钢制造。经调质处理后要求Ａ、Ｂ两止推面表面淬火 ,硬度 5 0ＨＲＣ。以前通过盐浴局部快速加热来实现表面淬火 ,但盐浴加热降低了材料的综合力学性能 ,不能达到表面淬火目的 ,所以决定改用中频感 Figure 1 shows the gear shaft is a key component of the turbine compressor, according to their service conditions, the use of 34CrNi3Mo steel. After the quenching and tempering requirements A, B two thrust surface hardening, hardness 50HRC. In the past, the surface quenching was achieved by rapid local heating in a salt bath. However, salt bath heating reduced the overall mechanical properties of the material and failed to achieve the purpose of surface hardening. Therefore, it was decided to switch to the intermediate frequency