一、前言为保证轴承钢具有必要的切削加工性能、较宽的淬火温度范围以及良好淬火组织和优异的疲劳性能,必须对轴承钢材进行球化处理以得到铁素体基体上均匀分布的细球状碳化物组织。碳化物的球化是在某一特定条件下碳化物溶解、析出、长大的过程,是碳由非平衡向平衡过渡的扩散过程。因此它需要较长的时间。百多年来所沿用的球化退火工艺基于轧后空冷的粗片状珠光体原始组 I. Preface In order to ensure the necessary machinability of bearing steel, wide quenching temperature range, well quenched structure and excellent fatigue performance, the bearing steel must be spheroidized to obtain a uniformly distributed spherical shape on the ferrite matrix Carbide organization. Carbide spheroidization is a process of dissolution, precipitation and growth of carbides under certain conditions. It is a diffusion process of carbon from a non-equilibrium to a balanced one. So it takes a long time. The spheroidizing annealing process used for over a hundred years is based on the crude lamellar pearlite primary set after air-cooling