1 National Engineering Laboratory of Additive Manufacturing for Large Metallic Components and Engineering Research Center, Beijing 100191, China; 2 Ministry of Education on Laser Direct Manufacturing for Large Metallic Components, Beijing 100191, China; 3 Beijing Engineering Technological Research Center on Laser Direct Manufacturing for Large Critical Metallic Component, Beijing 100191, China; 4 School of Materials Science and Engineering, Beihang University, Beijing 100191, China
Effect of thermal deformation on microstructure and properties of TC18 titanium alloy produced by laser additive manufacturing
1 National Engineering Laboratory of Additive Manufacturing for Large Metallic Components and Engineering Research Center, Beijing 100191, China; 2 Ministry of Education on Laser Direct Manufacturing for Large Metallic Components, Beijing 100191, China; 3 Beijing Engineering Technological Research Center on Laser Direct Manufacturing for Large Critical Metallic Component, Beijing 100191, China; 4 School of Materials Science and Engineering, Beihang University, Beijing 100191, China
摘要 Grain boundary of α phase damaged ductility of laser melting-deposited TC18 titanium alloy and grain boundary of α phases were difficult to break by nominal heat treatment. An extra thermal deformation was introduced to break the grain boundary of α phase with the improved mechanical property of TC18 titanium alloy fabricated by laser melting deposition technique. Results indicated that after thermal deformation, β grains in alloy seriously elongated. When sample was deformed at temperatures from 750 to 850 °C, α phase exhibited both rod and irregular morphologies with discontinuous distribution at grain boundary, and the subsequent heat treatment would lead to spheroidization of the α phase. However, after deformation at 900 °C, α phase transferred into β phase and the subsequent heat treatment would make continuous grain boundary of α phase reappear. The suitable hot deformation can effectively break the continuous grain boundary in laser melting-deposited TC18 alloy with respected improved ductility.
Abstract：Grain boundary of α phase damaged ductility of laser melting-deposited TC18 titanium alloy and grain boundary of α phases were difficult to break by nominal heat treatment. An extra thermal deformation was introduced to break the grain boundary of α phase with the improved mechanical property of TC18 titanium alloy fabricated by laser melting deposition technique. Results indicated that after thermal deformation, β grains in alloy seriously elongated. When sample was deformed at temperatures from 750 to 850 °C, α phase exhibited both rod and irregular morphologies with discontinuous distribution at grain boundary, and the subsequent heat treatment would lead to spheroidization of the α phase. However, after deformation at 900 °C, α phase transferred into β phase and the subsequent heat treatment would make continuous grain boundary of α phase reappear. The suitable hot deformation can effectively break the continuous grain boundary in laser melting-deposited TC18 alloy with respected improved ductility.
Xiao‑dong Li,Chang‑yue Qiu,Yu‑ting Liu, et al. Effect of thermal deformation on microstructure and properties of TC18 titanium alloy produced by laser additive manufacturing[J]. Journal of Iron and Steel Research International, 2020, 27(12): 1476-1484.
2020, Vol. 27 
