Study of the Chemical Composition and Microstructure of AISI 321/Cu/Ta/Ti Welded Joint

• Published in: Physics of metals and metallography 2020-11, Vol.121 (11), p.1112-1118
• Main Authors: Pugacheva, N. B., Orishich, A. M., Cherepanov, A. N., Senaeva, E. I., Trushina, E. B.
• Format: Article
• Language: English
• Subjects: Analysis; Carbon dioxide; Carbon dioxide lasers; Chemical composition; Chemistry and Materials Science; Copper; Diffusion; Intermetallic compounds; Laser beam welding; Lasers; Materials Science; Metallic Materials; Microstructure; Phase Transformations; Solid solutions; Structure; Tantalum; Tensile tests; Titanium; Titanium alloys; Titanium base alloys; Ultimate tensile strength; Welded joints; Welding
• ISSN: 0031-918X; 1555-6190
• DOI: 10.1134/S0031918X20110083

The chemical composition and microstructure of an AISI 321/Cu/Ta/Ti welded joint prepared by carbon dioxide laser is studied in this work. An analysis of the chemical composition showed that the Ta plate located between the Cu plate and Ti is the barrier for melting Ti in the welding pool. The welded joint consists of the Cu-based solid solution, austenite, and (Ta,Ti)(Fe,Cr) 2 and (Ta,Ti)Сu 3 intermetallic particles 10–50 µm in size. Tantalum actively interacts with the Fe-based melt. A diffusion zone consisting of β-Ti and (Ti,Ta) 2 Cu intermetallic particles forms near the boundary between the titanium alloy and the Ta plate. Joint fracture upon tensile tests occurs along the boundary between the (Fe + Cu) zone and Ta plate; the ultimate tensile strength is σ u = 215 MPa.