Analysis of element loss, densification, and defects in laser-based powder-bed fusion of magnesium alloy WE43

作     者：Faridreza Attarzadeh Ebrahim Asadi 

作者机构：Department of Mechanical EngineeringThe University of MemphisMemphisTN 38152United States 

出 版 物：《Journal of Magnesium and Alloys》 (镁合金学报（英文）)

年 卷 期：2022年第10卷第8期

页      面：2118-2136页

核心收录：

学科分类：08[工学] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0802[工学-机械工程] 080201[工学-机械制造及其自动化] 

基　　金：Tennessee Institute of Regenerative Medicine 

主　　题：WE43 magnesium alloy Additive manufacturing Powder-bed fusion Mg loss Vaporization Defects 

摘      要：It is well known that laser-based powder-bed fusion(L-PBF) additive manufacturing of magnesium(Mg) and its alloys is associated with high Mg loss due to vaporization(MgLoss) and high incidence of many types of defects in the manufactured parts/samples. Despite this,MgLoss, densification, and defect characteristics have not been holistically considered in the determination of the optimal values of L-PBF processing parameters for Mg and its alloys. This study presents a combined modeling and experimental approach applied for a widely used Mg alloy(WE43) to address this shortcoming in the literature. First, an experimentally calibrated model is proposed to determine MgLoss as a function of the L-PBF processing parameters. The model couples the temperature profile using a double ellipsoidal heat source with a Langmuir vaporization model and is calibrated using the width of the single-track L-PBF process and the measured Mglossusing inductively coupled plasma mass spectrometry(ICP-MS). Second, the densification of the samples is determined using a modification of the Archimedes method that considers the amount of MgLossin the calculation of the relative density. Third, a comprehensive and quantitative study is conducted on the relationships between the characteristics of porosity defects and the L-PBF processing parameters. Finally, the optimized L-PBF processing parameters are determined by considering the MgLoss, densification, and the characteristics of defects. The present study yields 0.23 wt.% MgLosscompared to 2 wt.% MgLossthat was reported in the previous studies. Furthermore, more than 99.5% densification is achieved while only ~2% and ~0.5% of the total defects are characterized as keyhole and lack of fusion defects, respectively.