【摘要】 通过建立合理的热处理工艺窗口,将低附加值的钢种升级为具有高强塑性的高附加值双相钢产品.以常规C-Mn钢热轧板坯为原料,经过热轧及冷轧后,进行连续退火实验.实验钢经过不同的冷却后过时效制度,形成了铁素体和马氏体组成的微观组织.当过时效温度在320℃以下时,避免了贝氏体组织的出现,并且马氏体相的体积分数随温度的降低而增加.实验钢的抗拉强度与马氏体相含量成正比,屈服强度和延伸率与其成反比,在320℃过时效处理下可获得最佳的综合力学性能,强塑积为18 254.6 MPa%.更多还原

【Abstract】 A high strength and ductility dual phase steel was developed from the traditional steel via establishing reasonable processing parameter w indow s,w hich transferred from low to high additional values. The continuous annealing specimen w as prepared from C-Mn steels by hot and cold rolling. The microstructure contained ferrite and martensite w as obtained by the intercritical anneal,controlled cooling and the subsequent different over-aging procedures. The bainite transformation w as avoided w hen the over-aging temperature w as low er than 320 ℃. The volume fraction of the martensite increased w ith the decrease of temperatures. The tensile strength w as proportional to the volume fraction of the martensites,w hereas the yield strength and elongation performanced an inverse relationship. The strength-ductility balance w as 18 254. 6 MPa% in the 320 ℃ over-aging procedure as a better mechanical property.更多还原