Improving mechanical properties of an explosive-welded magnesium/ aluminum clad plate by subsequent hot-rolling

As-explosive welded clad plates usually show poor ductility due to heavily deformed microstructures developed after explosive welding (EXW). In this study, the feasibility of improving mechanical properties of an EXWed Mg-6Al-1Zn-1Ca (AZX611)/Al-0.6Mg-0.6Si-0.1Fe (A6005C) (all in wt%) clad plate has been explored by subsequent hot-rolling. Increasing the thickness reduction per pass from 10% to 28% or decreasing the rolling temperature from 430 degrees C to 250 degrees C is shown to enhance tensile properties. The joint sheet rolled at 250 degrees C with a thickness reduction per pass of 28% shows a large fracture elongation of 15%, which is significantly higher than that of the as-EXWed clad plate, 1.2%. Microstructure characterization by means of scanning electron microscope, electron backscatter diffraction and transmission electron microscope reveals that the substantial improvement in ductility is intimately related to a significant reduction of the accumulated strain in AZX611 and A6005C alloy sheets and an elimination of the interface delamination formed during EXW. A certain degree of anisotropic mechanical properties is observed in all sheets regardless of rolling conditions, which can be ascribed to the mechanical anisotropy originated from the AZX611 and A6005C alloy sheets. (c) 2021 Elsevier B.V. All rights reserved.

Automated summary

This study explores the feasibility of improving the mechanical properties of explosive welded clad plates through subsequent hot-rolling and reveals that increasing the thickness reduction per pass or decreasing the rolling temperature can enhance tensile properties. Microstructure characterization shows that the significant improvement in ductility is closely related to the reduction of accumulated strain in the alloy sheets and the elimination of interface delamination formed during explosive welding.