Rapid Microstructure Homogenization of a Laser Melting Deposition Additive Manufactured Ti-6.5Al-3.5Mo-1.5Zr-0.3Si Alloy by Electropulsing

Dandan Ben; Huajie Yang; Jiabao Gao; Bingyu Yang; Yu'ang Dong; Xiangyu Liu; Xuegang Wang; Qiqiang Duan; Peng Zhang; Zhefeng Zhang

doi:10.3390/ma15207103

Rapid Microstructure Homogenization of a Laser Melting Deposition Additive Manufactured Ti-6.5Al-3.5Mo-1.5Zr-0.3Si Alloy by Electropulsing

Materials (Basel). 2022 Oct 13;15(20):7103. doi: 10.3390/ma15207103.

Authors

Dandan Ben^{1

2}, Huajie Yang^{1

2}, Jiabao Gao¹, Bingyu Yang^{1

2}, Yu'ang Dong¹, Xiangyu Liu³, Xuegang Wang¹, Qiqiang Duan¹, Peng Zhang^{1

2}, Zhefeng Zhang^{1

2}

Affiliations

¹ Shi-Changxu Innovation Center for Advanced Materials, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China.
² Department of Materials Science and Engineering, University of Science and Technology of China, Shenyang 110016, China.
³ Shenyang Zhongke Raycham Technology Co., Ltd., Shenyang 110200, China.

Abstract

The typical microstructure of the laser melting deposition (LMD) additive-manufactured Ti-6.5Al-3.5Mo-1.5Zr-0.3Si alloy (TC11) contains the heat-affected bands (HABs), the narrow bands (NBs) and the melting pools (MPs) that formed due to the reheating and superheating effects during the layer-by-layer manufacturing process. Characterization results indicated that the coarse primary α lath (α_p) and transformed β (β_t) structures were located in the HABs, while the fine basketweave structure was formed inside the MPs. The rapid modifications of microstructure and tensile properties of the LMD-TC11 via electropulsing treatment (EPT) were investigated. The initial heterogeneous microstructure transformed into a complete basketweave structure and the HABs vanished after EPT. Thus, a more homogeneous microstructure was achieved in the EPT sample. The ultrafast microstructural changes were mainly attributed to the solid state phase transformation during electropulsing. The tensile properties of the sample were basically stable, except that the yield strength decreased as EPT voltage increased. This study suggests that EPT could be a promising method to modify the microstructure and mechanical properties of the additive-manufactured alloys in a very short time.

Keywords: electropulsing; homogenization; laser melting deposition; microstructure; titanium alloy.

Grants and funding

Financial support from the National Natural Science Foundation of China (Grant No. 51975552, 52130002), Natural Science Foundation of Liao Ning (No. 2020-MS-007), the CAS Interdisciplinary Innovation Team (No. JCTD-2020-10) and the Liao Ning Revitalization Talents Program (No. XLYC1808027) is gratefully acknowledged.