正火碳—锰钢和晶粒细化钢的显微组织和机械性能之间的关系已在早先的文章中论述过。这类钢材经常用作结构材料,并且一般都具有铁素体—珠光体显微组织。业已表明,细的铁素体晶粒必然能得到高的屈服强度和良好的韧性。这就导致了特意用少量Nb,V,Al 或 Ti 细化晶粒的钢的出现,而 The relationship between the microstructure and mechanical properties of normalized carbon-manganese steels and grain-refined steels has been discussed in earlier articles. Such steels are often used as structural materials and generally have ferrite-pearlite microstructures. It has been shown that fine ferrite grains necessarily yield high yield strength and good toughness. This led to the advent of steels that had been deliberately refined with small amounts of Nb, V, Al or Ti