Brazing of 422 stainless steel using the AWS classification BNi-2 Braze alloy
- 438 Downloads
The study of brazing 422 stainless steel (422SS) using the AWS classification BNi-2 braze alloy as the filler metal is evaluated in the study. The BNi-2 braze alloy demonstrates excellent wettability on the 422SS substrate for temperatures exceeding 1025 °C. The brazed joint is primarily comprised of the Ni-rich matrix and chromium boride. Additionally, the B–Cr–Fe precipitates are formed at the interface between the braze and 422SS. Some Kirkendall porosity is also observed in the braze close to the interface, due to nonsymmetrical interdiffusion between the braze and 422SS substrate. Shear strengths of brazed joints are varied from 306 to 481 MPa. The infrared brazed specimen shows the highest shear strength among all brazed specimens. Increasing brazing temperature and/or time result in decreased shear strength of the brazed joint.
KeywordsBraze Alloy Braze Temperature Average Shear Strength 422SS Substrate Chromium Boride
The authors gratefully acknowledge the financial support of this research by the National Science Council (NSC), Republic of China under grant numbers, NSC 90-2216-E-259-003 and NSC 91-2216-E-259-002. EPMA analysis by Ms. Shu-Yueh Tsai in NSC Instrument Center, National Tsing Hua University, Hsinchu, Taiwan, is also gratefully appreciated.
- 1.Balmforth MC, Lippold JC (1998) Welding J 77:1sGoogle Scholar
- 2.Corbit RB, French SM (1997) Welding J 76:51Google Scholar
- 3.Armstrong D (1993) Welding World 31:426Google Scholar
- 5.Chandler H (1995) Heat Treater’s Guide: practices and procedures for irons and steels. ASM International, Metals Park, Ohio, p 763Google Scholar
- 6.Davis JR (1994). ASM specialty handbook: stainless steels. ASM International, Metals Park, OhioGoogle Scholar
- 8.Ginn BJ, Gooch TG (1998) Welding J 77:341sGoogle Scholar
- 9.Olson DL, Siewert TA, Liu S, Edwards GR (1993) ASM handbook Volume 6 welding, brazing, and soldering”. ASM International, Metals Park, OhioGoogle Scholar
- 10.Schwartz M (1995) Brazing: for the engineering technologist”. Chapman & Hall, New YorkGoogle Scholar
- 11.Humpston G, Jacobson DM (1993) Principles of soldering and brazing”. ASM International, Metals Park, Ohio, p 71Google Scholar
- 19.Lee RE (1993) Scanning electron microscopy and X-ray microanalysis. Prentice Hall, New York, p 130Google Scholar
- 20.Villars P, Prince A, Okamoto H (1995) Handbook of ternary alloy phase diagrams. ASM International, Metals Park, Ohio, p 5508Google Scholar