800 MPa级冷轧热镀锌双相钢的微观变形行为  

Micro-deformation behavior of 800 MPa cold rolled hot dip galvanized dual phase steel

作　　者：金光灿[1] 罗一平[1] 李锦[1] 

机构地区：[1]上海工程技术大学汽车工程学院,上海201620

出　　处：《材料热处理学报》2015年第9期143-147,共5页Transactions of Materials and Heat Treatment

摘　　要：利用透射电镜和EBSD技术对拉伸过程中800 MPa热镀锌双相钢的微观变形行为进行了研究,主要分析了不同变形量下的形变位错组态、铁素体形貌、马氏体形貌、铁素体晶粒尺寸和微观晶粒取向。研究结果表明:随着变形量的增加,铁素体晶粒内位错密度不断增加,进而产生缠结并形成位错胞;此后随着变形量的继续增大,位错胞数量增多,尺寸变小。随着变形量的增加,铁素体晶粒尺寸不断变小,当变形量为11%时,铁素体晶粒不再是规则的等轴形状,大部分的晶粒尺寸不到1μm;拉伸过程中,越来越多的位错塞积将大的铁素体晶粒分割成许多小尺寸的位错胞,导致大角度晶界比例下降,小角度晶界比例上升。The micro-deformation behavior of 800 MPa hot dip galvanized dual phase steel during the tensile process was studied. The deformed dislocations configuration, the ferrite morphology, the martensite morphology, the ferrite crystal grain size and the grain misorientation under different deformation amounts were analyzed by using transmission electron microscope and EBSD technology. The results indicate that with the deformation amount increases, the dislocation density in the ferrite grain increases continuousIy, then the dislocation entangled each other lead to the formation of dislocation cells. With the deformation amount continue to increase, the amount of dislocation cells increases, however, the size of the cells decreases. The ferrite generates yield deformation under 2% deformation amount, however, the martensite can not generate yield deformation until the deformation amount reaches to 11%. The martensite laths are not straight any more. With the deformation amount increases, the grain size of ferrite decreases continuously. The ferrite grains are no longer equiaxed, and most of them are less than 1 μm when the deformation amount reaches to 11%. Because more and more entangled dislocations separate large ferrite grains into many subgrains with small misoriention during the tensile process, the high-angle grain boundaries decrease and the small-angle grain boundaries increase.

关 键 词：冷轧热镀锌双相钢 微观变形 位错 位错胞 

分 类 号：TG142.1[一般工业技术—材料科学与工程]