The microstructure and property of Al-Si alloy and Al-Mn alloy bimetal prepared by continuous casting

The Al-10%Si alloy and Al-1%Mn alloy bimetal slabs are prepared by continuous casting. The microstructures around the interface are investigated, chemical composition distributions across the interface are detected, and tensile strengths are evaluated at the top, center and bottom regions of the bimetal slab. The results show that the Al-1%Mn alloy serves as a substrate of heterogeneous nucleation of Al-10%Si alloy at the bimetal interface. The metallurgical bonding is excellent without any discontinuities along the interface due to the diffusions of Si and Mn elements. The thickness of diffusion layers is about 40 mu m on average. The tensile strengths of the top, center and bottom regions of the bimetal slab tend to be uniform. (C) 2011 Elsevier B.V. All rights reserved.