对于薄壁的模具,以加热至相变温度以下快冷来缩小型腔的方法很难达到要求。后来我们根据高炭、高铬钢(Cr12Mo),在淬火冷却到M_H点前一瞬间体积小的道理,将图2的箍套在模具(图1)的外圆上,待回火冷却后,将凹凸模敲出,使其达到缩小的目的。采用这种方法,要注意以下几点: For thin-walled molds, the method of shrinking the cavity by rapid cooling below the phase transition temperature is difficult to meet the requirements. Later, according to the reason that the high-carbon and high-chromium steel (Cr12Mo) is small in size immediately before quenching and cooling to the point M_H, the ferrule in FIG. 2 is sheathed on the outer circle of the mold (FIG. 1) Punctuate the mold knocked out to achieve the purpose of narrowing. In this way, pay attention to the following points: