Differences in Properties between Hybrid Wire Arc Additive-Milling Subtractive Manufactured Aluminum and Magnesium Alloys

Abstract

Hybrid wire arc additive-milling subtractive manufacturing (HWMM) is an effective way to improve the quality of complex metal components, but the difference in the properties of the aluminum alloy and magnesium alloy fabricated by HWMM has been not addressed. In the paper, the differences in deposition accuracy and tensile anisotropy between the Al5Si Al and AZ31B Mg alloys were studied by using the HWMM method. Under the optimal parameters, the minimum surface roughness of the AZ31B sample was 146.1 μm, which was 90% higher than for the Al5Si sample. The differences in the tensile strength and elongation of the AZ31B sample were 32% and 56%, respectively, being 6 and 3.3 times higher than those of the Al5Si samples. According to the fracture behavior of the samples, the tensile anisotropy of both alloys was mainly attributed to defects such as incomplete fusion and porosity in the fusion line. However, there was obvious structural inhomogeneity in AZ31B samples, where the grain size difference between adjacent areas reached 40%. This led to the easier fracture of AZ31B samples. These results contribute to our understanding of the HWMM of light alloys.