金属间化合物对累积叠轧Mg/Al多层复合板材断裂过程的影响

Effect of intermetallic compounds on the fracture behavior of a Mg/Al laminated composite fabricated by accumulative roll bonding

摘要:

本文采用分步拉伸观测的方法研究了累积叠轧Mg/Al多层复合板材中界面金属间化合物对复合板材断裂过程的影响。结果表明：在单向拉伸过程中,Mg/Al界面处金属间化合物导致了裂纹的萌生和扩展,从而导致Mg/Al界面的分离；在后续拉伸过程当中,由于Mg层强度较低,首先产生颈缩失效,致使整个样品提前断裂。

Abstract:

Large amounts of massive cracked intermetallic compounds were observed at the interface of the laminated Mg/Al composite fabricated by accumulative roll bonding. Scanning electron microscopy revealed that the effect of these cracked intermetallic compounds dominated the fracture behavior of the accumulative roll bonded Mg/Al composite during uniaxial tensile testing. The results indicated that (i) obvious Mg/Al interface delamination was promoted by the cracked the intermetallic compounds, and (ii) the crack propagated into the softer Mg layer and leading to the rupture of Mg layer. These two factors led to premature failure of the laminated Mg/Al composite.