Interfacial Characteristics and Mechanical Behavior of Hybrid Manufactured AlSi10Mg–Al6061 Bimetal via Selective Laser Melting and Forging

Hybrid manufacturing (HM) uses additive manufacturing (AM) techniques to prepare complex or fine structures on traditional processing parts, which can fully utilize the advantages of AM to form complex parts, and the high efficiency and low cost of conventional processing methods in manufacturing regular components. A bimetal material was produced by selective laser melting (SLM) of AlSi10Mg on the deformed Al6061 alloy substrate in this study. Firstly, the interface characteristics of the two alloys were studied. The results show that a metallurgical interface with a thickness of 100–200 μm was formed as the result of the Marangoni convection during SLM preparation. In detail, the circular flow in the melt pool at the interface led to the dilution of alloying elements and the change of microstructure. Moreover, a suitable first-layer thickness can effectively suppress the hot cracks at the interfacial region. Based on the optimized results, the hybrid manufactured samples with different SLM processed volume ratios (SLM-part) to the substrate were prepared to study the mechanical properties and the deformation behavior of hybrid parts. The results show that the volume ratio of the SLM-part to the substrate had an influence on the strength and the elasto-plastic behavior by affecting the distribution of plastic deformation.