Microstructure and mechanical properties of Al-12Si and Al-3.5Cu-1.5Mg-1Si bimetal fabricated by selective laser melting

摘要

An Al-12 Si/Al-3.5 Cu-1.5 Mg-1 Si bimetal with a good interface was successfully produced by selective laser melting(SLM).The SLM bimetal exhibits four successive zones along the building direction:an Al-12 Si zone,an interfacial zone,a texture-strengthening zone and an Al-Cu-Mg-Si zone.The interfacial zone(fiber texture.Electron backscatter diffraction analysis shows that the grains grow gradually from the interfacial zone to the Al-Cu-Mg-Si zone along the building direction.Additionally,a strongfiber texture develops at the Al-Cu-Mg-Si side of the interfacial zone and disappears gradually along the building direction.The bimetal exhibits a room temperature yield strength of 267±10 MPa and an ultimate tensile strength of 369±15 MPa with elongation of 2.6±0.1%,revealing the potential of selective laser melting in manufacturing dissimilar materials.