组织对冷轧双相钢性能的影响

采用金相显微镜和透射电镜对两卷冷轧双相钢（7#和16#）的微观组织进行了观察并分析了其组织与性能的关系。结果表明，7#试样组织为多变形铁素体＋岛状马氏体；16#试样组织为饼形铁素体＋岛状马氏体＋大量游离渗碳体，铁素体的尺寸较大，数量较多，马氏体岛的数量较少，尺寸偏大，发生分解的马氏体岛数量较多。16#试样组织未完全再结晶导致组织粗大、细晶强化贡献弱是其屈服强度较低的主要原因；大量未奥氏体的渗碳体导致马氏体岛数量少及发生碳化物分解的马氏体量多是其抗拉强度低的主要原因。

Influence of Microstructure of Cold--Rolled Dual Phase Steel on the Mechanical Properties

The microstructures of the two coils （7 # andl6 # ） of cold--rolled dual--phase steels were observed by opncat microscope and transmission electron microscope, and the relation between the microstructure and properties were ana- lyzed. The results show that： the microstructures of sample 7 # are composed o[ polygonal [errites and martensite islands; the microstructures of sample 16# are composed of pancake ferrites, martensite islands and lots of free cementite. The sizes of ferrites are bigger, the number of it is larger; The sizes of martensite are also larger, the number of it is less, and parts of martensites decomposed into bainite. Coarse microstructure of sample 16 # leads to the weaker fine--grained strengthing effect, which is the main reason causing the sample having lower yield strength. Lots of free cementite without austenization induces to the little volume of matensite with lower carbon content, and parts of martensites decompose into bainite, which are the main reasons that the tensile strength is lower.