摘要
采取感应加热的方法异温轧制制备钢/铝复合板,整个过程处于一种Ar气保护氛围,研究了钢/铝复合板的结合性能和微观组织,并与冷轧工艺进行对比,分析了异温轧制工艺对结合性能的影响。结果表明:异温轧制的复合板由于钢层加热温度高于钢的动态再结晶温度,轧后碳钢组织出现等轴晶粒,发生了动态回复和再结晶,并且在钢侧近界面处产生一层平均晶粒尺寸约为5μm的等轴细晶区,相比于冷轧复合板,大大降低了复合板的加工硬化现象。异温轧制的钢/铝复合板微观界面贴合紧密,无孔洞和间隙,跨界面的Al和Fe元素扩散宽度达到2.4μm,复合板达到了良好的冶金结合状态,并且近界面的细晶区改善了板材性能,使得异温轧制复合板的剪切强度远高于冷轧板,在45%压下率下达到了85 MPa,是同等压下率冷轧复合板剪切强度(12 MPa)的7倍,冷轧板断裂发生在钢/铝结合面处,为脆性断裂,而异温轧制的复合板断裂发生在铝合金基体,剪切断面存在大量韧窝,呈现塑性断裂特征。
Both cold-rolled and hot-rolled steel/aluminum laminated composites exhibited obvious strain-hardening of steel layer because the rolling temperature,limited by the melting point of aluminum(about 660℃),was lower than dynamic recrystallization temperature of steel(about 710℃).This led to poor deformation ability of composite plates and subsequent processing cracks.And the initial bonding of cold-rolled steel/aluminum composite plates usually required more than 50%highly first pass reduction,which resulted in high requirement for rolling mill capacity,especially for medium or thick size composite plates.To solve above two problems simultaneously,in this study,the steel/aluminum composite plates were prepared by differential temperature rolling(DTR)with induction heating in an argon atmosphere.The bonding properties and microstructure of the steel/aluminum laminated composites were studied,and the effect of DTR process on the bonding properties was analyzed compared with the cold rolling process.The results show that dynamic recovery and recrystallization occurred with equiaxed grains appearing in the structure of the rolled carbon steel due to the higher heating temperature of the steel layer,and an equiaxed fine grain zone with an average grain size of approximately 5μm was formed near the interface of the steel side,which greatly reduced the hardening phenomenon of the laminated composites compared with the cold rolled clad plate.The micro-interface of DTR steel/aluminum clad plate was tightly bonded without holes and gaps.The diffusion width of Al and Fe elements across the interface reached2.4μm,indicating the clad plate achieved a good metallurgical bonding state,and the fine grained zone near the interface improved the properties of the sheet.The combined effect made the shear strength of the DTR clad plates much higher than that of the cold-rolled plate.At 45%reduction,the shear strength of DTR composite plate reached 85 MPa,which was 7 times of cold-rolled composite plate with the same reduction(12 M
作者
肖宏
许朋朋
祁梓宸
吴宗河
赵云鹏
XIAO Hong;XU Pengpeng;QI Zichen;WU Zonghe;ZHAO Yunpeng(National Engineering Research Center for Equipment and Technology of Cold Strip Rolling,Yanshan University,Qinhuangdao 066004,China)
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
2020年第2期231-239,共9页
Acta Metallurgica Sinica
基金
国家自然科学基金项目No.51474190
河北省研究生创新项目No.CXZZBS2019046.
关键词
钢/铝复合板
感应加热
异温轧制
剪切强度
显微组织
steel/aluminum composite plate
induction heating
differential temperature rolling
shear strength
microstructure
