Effect of Energy Density on Defects and Mechanical Properties of AlSi10Mg Alloy Fabricated by Selective Laser Melting

doi:10.3901/JME.2020.24.096

Abstract

Abstract: The influence of energy density on relative density of the formed AlSi10Mg alloy is analyzed, and the types as well as sizes of internal defects in AlSi10Mg samples are counted by micro-nano CT detection together with energy dispersive spectrometer (EDS) analysis. The three-dimensional distribution and causes of defects with the samples are analyzed, and the main factors affecting the relative density as well as internal defects of selective laser melting fabricated AlSi10Mg alloy are put forward. It is shown that appropriate laser energy input is the key to obtain high density. When the laser energy density is in the range of 47.62-50.00 J/mm³, the samples have the highest density, the inclusion defects disappear and the maximum size of the hole defects reduce to 0.056 mm. The causes of hole defects are mainly related to unmelted powder, hollow powder and oxides. The average tensile strength and elongation of AlSi10Mg alloy fabricated under the optimum laser energy density range are above 294 MPa and 8.0%, respectively, which are higher than those of cast AlSi10Mg alloy.

Key words: selective laser melting, AlSi10Mg, relative density, hole defects, tensile properties

CLC Number:

TN249

YAN Taiqi, TANG Pengjun, CHEN Bingqing, GAO Xiangxi, CHU Ruikun, XIONG Huaping. Effect of Energy Density on Defects and Mechanical Properties of AlSi10Mg Alloy Fabricated by Selective Laser Melting[J]. Journal of Mechanical Engineering, 2020, 56(24): 96-105.

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