Interface microstructure evolution and bonding strength of TC11/γ-TiAl bi-materials fabricated by laser powder deposition

• Published in: Rare metals Vol. 35; no. 6; pp. 456 - 462
• Main Authors: Xu, Zhi-Jun, Zhang, Yong-Zhong, Liu, Ming-Kun, Gong, Xin-Yong
• Format: Journal Article
• Language: English
• Published: Beijing Nonferrous Metals Society of China 01-06-2016
• Subjects: Aluminum; Biomaterials; Chemistry and Materials Science; Deposition; Energy; Evolution; Lasers; Materials Engineering; Materials Science; Metallic Materials; Microstructure; Molybdenum; Nanoscale Science and Technology; Physical Chemistry; TiAl基; Titanium; Titanium base alloys; Transformations; 双材料; 微观组织演变; 沉积技术; 激光; 界面; 粉末; 粘结强度; TC11 titanium alloy; γ-TiAl alloy; Laser powder deposition; Bi-material; Interface
• ISSN: 1001-0521; 1867-7185
• DOI: 10.1007/s12598-014-0243-1

Laser powder deposition was applied to fabricate the Ti-6.5Al-3.5Mo-1.5Zr-0.3Si （wt%）/Ti-47Al- 2Cr-2Nb-0.2W-0.15B （at%） bi-material system. The asdeposited TC11 alloy shows a basket-wave-like morphology while the as-deposited y-TiAl alloy consists of fully α2/γ lamellar microstructures. Regarding the thermal mismatch between TC11 and γ-TiAl during processing, the interface microstmcture evolution was concerned. The transformation pathway was illustrated. It is found that the content changes of Al elements and β-stabilizers Mo, Cr, and Nb are responsible for the evolution of microstructures at the interface. The fracture surfaces are located at the y-TiAl side. The bi-material shows a brittle-fracture manner, with the ultimate tensile strength of 560 MPa.