改善35CrMnSi碟片翘曲畸变的热处理工艺

Heat treatment process for improving warpage distortion of 35CrMnSi steel disc

利用模具加压通水冷却降低35CrMnSi碟片淬火时产生的翘曲畸变,研究了不同淬火温度和加载压力下的显微组织、畸变量和硬度。结果表明:当淬火温度为850℃和910℃、加载压力为8 MPa时,叠片的显微组织为板条状马氏体+少量针状马氏体,未观察到大块状的未溶铁素体、魏氏组织、网状铁素体和针状铁素体;最佳的热处理工艺参数为淬火温度890℃、加载压力10 MPa,此时碟片的畸变量为11μm,硬度为55 HRC。由于碟片在模具中冷却时变形量受到了良好的控制,畸变量符合技术要求,一次交检合格率达到了98%,取得了满意的应用效果。

Die-pressurized water-cooling process was used to reduce the warpage distortion of 35 CrMnSi steel disc during quenching, and the microstructure, distortion and hardness of the disc under different quenching temperatures and pressures were studied. The results show that the microstructure of the disc is lath martensite and a small amount of acicular martensite when quenching at 850 ℃ and 910 ℃ with pressure of 8 MPa, and no undissolved ferrite, Widmanstatten structure, reticulated ferrite and acicular ferrite are observed. The optimum heat treatment process is quenching at 890 ℃ with pressure of 10 MPa, under which the distortion is 11 μm and the hardness is 55 HRC. Due to the fact that the deformation of the disc in die-pressurized water-cooling process is well controlled and the distortion can meet the technical requirement, the pass rate of one-time inspection reaches 98%, and satisfactory application results is achieved.