一、前言 40C_r钢气门小端面高频淬火超深,是我厂热处理存在的一大难题。一九八四年至一九八五年期间,我们对气门小端面淬火作了一些试验,结果超深比率仍达40～60％。仅此工序、每年造成产品返修费用近四万元,为迅速解决淬火质量问题,我们进行了可行性分析和探索。 二、杆件原始组织状态及技术要求 First, the preface 40C_r steel valve small end surface quenching ultra-deep, is my factory heat treatment of a major problem. From 1984 to 1985, we conducted some experiments on the valve facet quenching. As a result, the ultra-deep ratio still reached 40-60%. This process alone, resulting in product repair costs nearly 40,000 yuan each year, in order to quickly solve the problem of quenching quality, we conducted a feasibility analysis and exploration. Second, the original state of the rod and the technical requirements