Development of novel titanium alloys with a fully equiaxed grain structure and ultrahigh yield strength through high-throughput laser additive manufacturing

Chunlei Qiu*, Yanjun Liu, Xu Chen, Wenqi Dong

School of Materials Science and Engineering, Beihang University, Beijing, 100191, China

EXTENDED ABSTRACT: It is well known that the state-of-the-art titanium alloys are liable for development of columnaigrains and strong texture during additive manufacturing (AM) due to steep thermal gradients in melt pools, lcading tomechanical property anisotropy in as-fabricated parts. In this study, multiple titanium alloys were designed based onconstitutional supercooling solidification theory and d-electron theory with the aim of developing high-strength titaniumalloys special for AM processing and various critical applications, i.e., to achieve both fully equiaxed grain structures and hig!strengths in the AM-processed alloys. Fe and Co have been selected as the main solute elements to titanium and a number of Ti-Fe-Co-Mo samples were fabricated through high-throughput laser additive manufacturing approach (HTAM). Withproper processing conditions, several novel titanium alloys with fully equiaxed grains and ultrahigh yield strength have beensynthesized by HTAM.These alloys with different compositional designs demonstrate different deformation mechanisms(slipping or twinning) but exhibit equally high strengths and good ductility. The microstructural evolution, tensile propertiesand deformation mechanisms of the synthesized alloys have been extensively investigated and will be reported in detail. 

Brief Introduction of Speaker

邱春雷,北京航空航天大学材料科学教授、博士生导师。于 2010年获得英国伯明翰大学冶金与材料学院博士学位。2011~ 2016 年在伯明翰大学从事研究员工作。2016~2017 年任职于英国卡迪夫大学工程学院助理教授。过去十余年主要从事先进近净成形技术研究,包括激光增材制造及热等静压近净成形技术。作为主要研究者曾参与英国及欧盟多个主要近净成形及金属增材制造项目,先后与英国罗尔斯- 罗易斯、BAE 系统公司、法国赛峰公司、空客、泰雷兹公司、欧洲宇航局、北京航空材料研究院等国内外主要航空航天公司及机构开展合作研究。入选2016 年国家青年千人计划,担任国家重点研发计划项目“高性能复杂合金激光冶金高通量制备原理与装备”项目负责人。在 ActaMaterialia,Additive Manufacturing 等期刊上发表 50 多篇SCI论文,他3500多次,H 因子 =26,拥有1 项美国发明专利,1 项英国发明专利,6 项中国发明专利。