MICROSTRUCTURE AND MECHANICAL PROPERTIESOF WIRE ARC ADDITIVE MANUFACTURING Al‒ 5SiALLOY

Al ‒ 5Si alloy (4043), because of its good formability, high specific strength, and excellent corrosion resistance, is widely used in aerospace and automotive engineering. With the research and application of additive manufacturing technology such as wire/power laser additive manufacture, wire/power arc additive manufacture and so on. In this study, the Al ‒ 5Si alloys have been used as raw materials for additive manufacturing research andwire arc additive manufacturing system equipped with 3D path simulation software, arc heat source and robot controlling platform is adopted to fabricate Al ‒ 5Si alloy. The microstructure and mechanical properties of this Al ‒ 5Si alloys are investigated. The x-ray diffraction results revealthat the as-deposited alloy is composed of α-Al, Si phase and intermetallic phase Al9Si. According to optical microscope observation, it is found that as the deposition height increases, the eutectic Si phase is significantly coarsened and the columnar grains are gradually refining and transforming into finer equiaxed grains, and the grain size of the microstructure of the inter-layer regions is smaller than that of the inner-layer regions at any height. The average micro-hardness presents 47.5 ± 3.4 Hv, and the strength properties present only 1.6 –5.0 MPa difference in ultimate tensile strength, 2.4 –5.9MPa difference in yield strength and 0.1 –1.1 % difference in elongation between tensile samples cut from different locations. It further indicates the better stability of wire arc additive manufacturing samples, and it is a better manufacturing method to fabricate metal parts.