中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 32 No. 9 September 2022 |
（1. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China;
2. Guangzhou Sailong Additive Manufacturing Co., Ltd., Guangzhou 510700, China;
3. State Key Laboratory of Porous Metal Materials, Northwest Institute for Nonferrous Metal Research, Xi’an 710016, China）
Abstract:The effect of porosity on compressive, bending, and tensile properties of the porous tantalum scaffolds fabricated by electron beam powder bed fusion (EB-PBF) was investigated. The porous tantalum scaffolds with porosity from 69% to 77.8% were obtained by varying the designed porosity and adjusting the processing parameters. It is found that the pores and unfused powder decrease with the increase of deposited energy density. The decrease of porosity leads to an improvement in mechanical properties. The relevancy between compressive/bending/tensile yield strength and relative density can be described appropriately by exponential model, while the relationship between elastic modulus and relative density is in good agreement with the Gibson-Ashby model. All the porous tantalum scaffolds exhibit good ductility in compressive, bending and tensile tests. No fragmentation of struts is observed during the compression process, but cracks are formed on the strut surface after 90° bending, mainly due to the high sensibility to defects caused by the oxide.
Key words: porous tantalum scaffold; electron beam powder bed fusion; porosity; mechanical properties; Gibson- Ashby model
