Effect of processing parameters on solidification defects behavior of laser deposited AlSi10Mg alloy

• Published in: Vacuum 2019-09, Vol.167, p.471-478
• Main Authors: Gao, Yuan, Zhao, Jibin, Zhao, Yuhui, Wang, Zhiguo, Song, Hongwu, Gao, Mengqiu
• Format: Article
• Language: English
• Subjects: AlSi10Mg alloy; Laser deposition; Pore defect; Processing parameter
• ISSN: 0042-207X; 1879-2715
• DOI: 10.1016/j.vacuum.2019.06.042

In order to investigate the influences of different processing parameters to the defects feature and microstructure of the Laser Direct Metal Deposited AlSi10Mg alloy parts, AlSi10Mg alloy depositing experiments were carried out using various scanning speed, carrier gas flow rate and laser incidence directions. The effects of the above parameters to the inner defects feature and microstructure of the deposited layers were obtained through analyzing the metallographic samples. And the causes of the pore defects inside the samples were analyzed and speculated. To verified the conclusions, tensile tests were implemented. It is discovered that increasing the scanning speed properly during depositing can reduce the pores generated by both hydrogen and trapped external gases, and have positive impact to the microstructure and microhardness of the samples. In addition, increasing the carrier gas flow rate will dramatically worsen the defects feature, and deflecting the laser incidence direction to obtuse angle to the laser scanning direction can lessen the number and the size of pore defects. •The effect of processing parameters on pore defects behavior and microstructure were studied.•The mechanism of the formation of pore defects were speculated.•The microstructure and property of laser forming repaired ZL101 alloy were studied.