一、绪言当把钢加热到奥氏体温度区时,抑制此时生成的奥氏体晶粒(下面简称Υ晶粒)粗化,对防止降低钢的韧性有重要的意义。以前报道了一些有效利用AIN、Nb(CN)等的研究。关于借助析出物抑制晶粒粗化的机理,已由GIadman提出了一般理论,导出了对抑制晶粒粗化有效的析出物的临界粒度、体积百分率与晶粒大小之间的相互关系的公式。 I. INTRODUCTION When the steel is heated to the austenite temperature zone, it is of great significance to prevent the austenite grains (hereinafter referred to as the Y grains) from being roughened at this time and prevent the reduction of the toughness of the steel. We have previously reported some studies that make effective use of AIN, Nb (CN), and others. With regard to the mechanism by which precipitates inhibit grain coarsening, a general theory has been proposed by GIadman to derive a formula for the relationship between the critical grain size, the volume fraction and the grain size of precipitates that are effective in suppressing grain coarsening.