Effect of Annealing Temperature on Microstructure and Tensile Properties of AlSi10Mg Alloy Fabricated by Selective Laser Melting

doi:10.3901/JME.2020.08.037

Abstract

Abstract: The effect of annealing temperature on microstructure and tensile properties of AlSi10Mg alloy fabricated by selective laser melting (SLM) technology is studied. The experimental results show that the net-like eutectic Si in the as-built samples is fractured and roughened during annealing. With the increase of annealing temperature, the net-like eutectic Si is spheroidized and evenly distributed in Al matrix as particles, and the dispersive secondary Si particles in Al matrix gradually dissolve and disappeare. After annealing treatment, the elongation of SLM fabricated AlSi10Mg alloy is greatly increased, and the fracture surface is characterized by dimples. After 270-280℃ annealing for 2 h, the elongation reaches above 15.7%(X/Y direction) and 12.7%(Z direction), with the tensile strength still remained at a high level(300 MPa), which indicates a good strength/plasticity match. Based on the fracture analysis results of tensile samples, it is believed that the main reasons for the crack initiation are the as-built defects including unmelted powder, pores and oxides.

Key words: selective laser melting, AlSi10Mg, annealing, microstructure, tensile properties

CLC Number:

TN249

YAN Taiqi, TANG Pengjun, CHEN Bingqing, CHU Ruikun, GUO Shaoqing, XIONG Huaping. Effect of Annealing Temperature on Microstructure and Tensile Properties of AlSi10Mg Alloy Fabricated by Selective Laser Melting[J]. Journal of Mechanical Engineering, 2020, 56(8): 37-45.

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