Additive manufacturing of Ti-6Al-4V lattice structures with high structural integrity under large compressive deformation

作者：Yang, Kun; Wang, Jian; Jia, Liang; Yang, Guangyu; Tang, Huiping^*; Li, Yuanyuan^*

来源：Journal of Materials Science & Technology, 2019, 35(2): 303-308.

DOI：10.1016/j.jmst.2018.10.029

• Selective electron beam melting
• Ti-6Al-4V
• Lattice structures
• Ductility
• Annealing
• Beta annealing

Additively manufactured Ti-6Al-4V lattice structures have found important niche applications. However, they often show insufficient compressive ductility or insufficient structural integrity. In this study, a batch of 45 octahedral Ti-6Al-4V lattice structures was manufactured in three different strut diameters (0.5, 1.0, 1.5 mm) by selective electron beam melting (SEBM). The influence of post-SEBM annealing on the compressive deformation characteristics of the lattice structure was investigated. The as-built Ti-6Al-4V lattices fragmented when the compressive strain reached 13%-23% depending on strut diameter. Annealing at 950 degrees C (beta transus temperature: 995 degrees C) only slightly improved the compressive ductility of the lattice structures. However, annealing at 1050 degrees C (beta-annealing) fundamentally changed the compressive deformation mode of the lattice structures. The resultant compressive stress-strain curve was featured by a long smooth plateau and no facture occurred even after significant densification of the lattice structure had taken place (>50% of compressive strain).

• 出版日期2019-2
• 单位吉林大学; 西北有色金属研究院