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High-entropy alloys (HEA), a new generation alloy system offer superior mechanical properties with solid solution strengthening. AlxCoCrFeNi-HEA is one such system being received more attention because of its specific yield strength and ductility. In the present work, Al0.5CoCrFeNi-HEA was prepared by vacuum arc melting. The laser beam welding (LBW) was carried out on 1mm thick forged and homogenized HEA, with a beam power of 1.5 kW and at a traverse speed of 600 mm/min. The microstructural features of different regions of the weld were studied using scanning electron microscopy. The homogenized Al0.5CoCrFeNi-HEA have shown equiaxed grains of average size 60 μm. The weld metal showed a typical weld fusion zone microstructure with dendritic structure with a reduction in BCC phase due to minimal Al and Ni segregation ratio at interdendrites. Micro-chemical analysis with energy dispersive spectroscopy confirmed that there was no major segregation of elements in the weld fusion zone. The microhardness survey performed across the weld evidenced a reduction in hardness, as a consequence of significant reduction in Al-Ni rich hardening factor.

In this study, a combination of Al–12Si and Al–20Si (Al–(12-20)Si) alloys was fabricated by selective laser melting (SLM) as a result of increased component requirements such as geometrical complexity and high dimensional accuracy. The microstructure and mechanical properties of the SLM Al–(12-20)Si in as-produced as well as in heat-treated conditions were investigated. The Al–(12-20)Si interface was in the as-built condition and it gradually became blurry until it disappeared after heat treatment at 673 K for 6 h. This Al–(12-20)Si bi-material displayed excellent mechanical properties. The hardness of the Al–20Si alloy side was significantly higher than that of the Al–12Si alloy side and the disparity between both sides gradually decreased and tended to be consistent after heat treatment at 673 K for 6 h. The tensile strength and elongation of the Al–(12-20Si) bi-material lies in between the Al–12Si and Al–20Si alloys and fracture occurs in the Al–20Si side. The present results provide new insights into the fabrication of bi-materials using SLM.