【摘要】 Cr强烈地引起30CrNi5MoV钢的“软化”,在相同的试验条件下,随着Cr含量的增加（0.22—1.61％Cr）,钢的条件比例极限(σP₅₀)呈直线下降的趋势。用光学显徽镜、透射电镜和相分析等方法研究了这种“软化”效应。结果表明,“软化”主要是由于Cr改变溶质原子在α-Fe中的溶解度、粗化马氏体的亚结构及降低碳化物的长度与碳化物间距的比值从而降低σp₅₀的结果。更多还原

【Abstract】 The influence of Cr contents on the softening effect of steel 30CrNi5MoV was investigated by using optical microscopy, TEM and phase analysis. The conditional proportion limit, σ_p50, of the steel falls sharply as the increasing of Cr contents in the range 0.22—1.61％ under same other experimental conditions. It was deduced that its falling rate is expressed as: σ_p50=1352—245×Cr％. The softening effect may be substantially resulted from that Cr changes the solubility of solute in α-ferrite, coarsens the martensitic substructure and reduces the ratio of the grain size of carbides to their interparticle spacings.更多还原