一前言等温淬火近年来在机械制造上已取得了日益广泛的应用。等温淬火热处理操作极为简便,在热处理时由于奥氏体到针状托氏体的转变系在等温盐浴中于整个工件的截面上同时进行,因此淬火热应力和组织应力几乎全部消除,保证工件在淬火时不会发生畸变及废品的危险。同时等温淬火后的钢铁另件具有极为优良而突出的机械性能,例如在中等或高的硬度下,有足够的强度及良好的冲击韧性,抗疲性和弹性极限,以及高的耐磨性,对于截面细小而形 A foreword Isothermal quenching In recent years in machinery manufacturing has made an increasingly wide range of applications. Isothermal Quenching heat treatment operation is extremely simple, in the heat treatment due to austenite to acicular trochanter transformation in isothermal salt bath in the entire workpiece cross-section at the same time, so the quenching thermal stress and tissue stress almost all to ensure that the workpiece Quenching does not occur in the distortion and the danger of waste. At the same time, the steel after isothermal quenching has extremely excellent and outstanding mechanical properties, such as moderate or high hardness, sufficient strength and good impact toughness, fatigue resistance and elastic limit, and high wear resistance, Small and shaped for the cross section