论文部分内容阅读
研究了精密气体渗碳等温淬火工艺对18Cr2Ni4WA钢渗层硬度、深度及显微组织的影响。结果表明,随着总渗碳保温时间的延长,渗层深度增加,但硬度曲线变得平缓;在相同总保温时间的情况下,强渗时间越长,渗层越深;而当扩散时间相同时,强渗时间越长,淬火后表层的硬度较低。优化的精密气体渗碳工艺为:保温温度均为910℃,强渗阶段碳势1.20%,保温3 h;扩散阶段碳势0.80%,保温1 h,渗碳后进行等温淬火,可以获得(1.2±0.1)mm渗层深度。渗碳淬火后渗层组织良好。该工艺成功应用于衬套零件的实际生产,满足了设计要求。
The effects of the austempering process of precision gas carburization on the hardness, depth and microstructure of 18Cr2Ni4WA steel were studied. The results show that with the increase of the total carburization holding time, the depth of the layer increases, but the hardness curve becomes gentle. In the case of the same total holding time, the longer the hardening time is, the deeper the layer becomes. When the diffusion time At the same time, the longer the hardening period, the lower the hardness of the surface after quenching. The optimized precision gas carburizing process is as follows: the holding temperature is 910 ℃, the carbon potential in the intensive infiltration stage is 1.20% and the holding time is 3 h; the carbon potential in the diffusion stage is 0.80%, holding for 1 h, then isothermal quenching after carburizing, ± 0.1) mm Penetration depth. Carburized after quenching the disseminated tissue well. The process has been successfully applied to the actual production of bushing parts to meet the design requirements.