Zhang Ting, Xu Hao, Li Zhongjie, She Huan, Du Dafan, Dong Anping, Xing Hui, Wang Donghong, Zhu Guoliang, Sun Baode
Shanghai Key Lab of Advanced High-temperature Materials and Precision Forming, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, PR China.
School of Mechanical Engineering, Shanghai Institute of Technology, Shanghai, 201418, PR China.
J Mech Behav Biomed Mater. 2020 Sep;109:103842. doi: 10.1016/j.jmbbm.2020.103842. Epub 2020 May 12.
In this work, TC4/TNTZO multi-layered composite as well as TNTZO and TC4 alloys were prepared by direct laser deposition (DLD) to investigate the microstructure, mechanical properties and in vitro bioactivity. The microstructure characterization shows that the multi-layered material is free of cracks and intermetallics while the interface is metallurgically bonded. The fine microstructure was observed in TC4 layer of the TC4/TNTZO multi-layered material, and a large amount of α' martensite exists in the transition zone. Different from the single β phase cellular arrays in the DLD-ed TNTZO alloy, α″ martensite with high volume content formed at the cellular grain boundary in TNTZO zone of DLD-ed TC4/TNTZO. The elastic modulus of the DLD-ed TC4/TNTZO is 64 GPa, decreased about 45% compared to the DLD-ed TC4. The tensile yield strength and elongation along the printing direction are up to 789 MPa and 7%, which are 12% higher than the tensile yield strength of DLD-ed TNTZO and 61% higher than the elongation of DLD-ed TC4 respectively. Moreover, the DLD-ed TC4/TNTZO shows good in vitro bioactivity. The TC4/TNTZO multi-layered composite fabricated by DLD can be regarded as a potential candidate to integrate the advantages of the two Ti-base alloys for application in the biomedical field.
