Brazing of Martensitic Stainless Steel to Copper Using Electroplated Copper and Silver Coatings

  • T. VenkateswaranEmail author
  • Vincent Xavier
  • D. Sivakumar
  • Bhanu Pant
  • P. K. Jayan
  • G. D. Janaki Ram


Brazing of 3 mm thick sheets of low-carbon martensitic stainless steel and Cu-Cr-Zr-Ti alloy was attempted using electroplated coatings of Cu and Ag. Ni coating of 5 µm thick was provided on the MSS base metal to enhance the wettability. Brazing experiments were carried out at 985 °C for a holding of 15 min. Detailed microstructural studies, hardness, lap-shear, tensile, and pressure tests were carried out on the brazed joints. The reaction between the Cu and Ag coatings lead to the formation of in situ braze metal. The microstructure of the braze metal was found to consist of Cu-rich primary alpha (αP) and Ag-rich eutectic mixture (β + αE). In lap-shear tests, the brazed joints produced with an overlap of 9 and 6 mm were found to fail in copper base metal, while the joints produced with an overlap of 3 mm failed in the braze metal exhibiting a lap-shear strength of 147 MPa. In tensile tests, the butt brazed joints were found to fail in copper base metal as well with an average tensile strength of 213 MPa. The braze metal hardness was found to be higher than the hardness of the copper base metal. In pressure tests, the brazed panels were found to survive a pressure of 750 bar without undergoing any damage. These results show that electroplated coatings of Cu and Ag can be advantageously utilized for brazing of large, complex-shaped parts such as thrust chambers in space industry.


Ag coating brazing Cu coating martensitic stainless steel 



The authors would like to thank Mr. N. R. V. Kartha, Satish Dhawan Visiting Scientist, and Mr. N. Venkatesh, Project Director/SCP of Liquid Propulsion System Center, Trivandrum, for providing technical support.


  1. 1.
    D.K. Huzel and D.H. Huang, Modern Engineering for Design of Liquid-Propellant Rocket Engines, in AIAA (1992).Google Scholar
  2. 2.
    M.E. Boysan, A. Ulas, K.A. Toker, and B. Seckin, Comparison of Different Aspect Ratio Cooling Channel Designs for a Liquid Propellant Rocket Engine, in 3rd International Conference on RAST’07 (IEEE, 2007), pp. 225–230.Google Scholar
  3. 3.
    W.R. Wagner and J.M. Shoji, Advanced Regenerative-Cooling Techniques for Future Space Transportation Systems, in 11th Propulsion Conference., AIAA (1975), p 1247Google Scholar
  4. 4.
    A. Ulas and E. Boysan, Numerical Analysis of Regenerative Cooling in Liquid Propellant Rocket Engines, Aerosp. Sci. Technol., 2013, 24, p 187–197CrossRefGoogle Scholar
  5. 5.
    T. Nguyentat, W.A. Hayes, T.O. Meland, E.M. Veith, and D.L. Ellis, Fabrication of a Liquid Rocket Combustion Chamber Liner of Advanced Copper GRCop-84 via Formed Platelet Liner Technology, in 42nd AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit (2006)Google Scholar
  6. 6.
    T. Fukikoshi, Y. Watanabe, Y. Miyazawa, and F. Kanasaki, Brazing of Copper to Stainless Steel with a Low-Silver-Content Brazing Filler Metal, IOP Conf. Ser. Mater. Sci. Eng., 2014, 61, p 012016CrossRefGoogle Scholar
  7. 7.
    S.V. Lasko and N.F. Lasko, Soldering metals, 4th ed., Mechanical Engineering Publishers, Moscow, 1988Google Scholar
  8. 8.
    Y. Zheng, N. Li, J. Yan, and Y. Cao, The Microstructure and Mechanical Properties of 1Cr17Ni2/QAl7 Brazed Joints Using Cu-Mn-Ni-Ag Brazing Alloy, Mater. Sci. Eng. A, 2016, 661, p 25–31CrossRefGoogle Scholar
  9. 9.
    R.K. Roy, S. Singh, M.K. Gunjan, A.K. Panda, and A. Mitra, Joining of 304SS and Pure Copper by Rapidly Solidified Cu-Based Braze Alloy, Fusion Eng. Des., 2011, 86, p 452–455CrossRefGoogle Scholar
  10. 10.
    L. Sanchez, D. Carrillo, E. Rodriguez, F. Aragon, J. Sotelo, and F. Toral, Development of High Precision Joints in Particle Accelerator Components Performed by Vacuum Brazing, J. Mater. Process. Technol., 2011, 211, p 1379–1385CrossRefGoogle Scholar
  11. 11.
    R.K. Choudhary and P. Mishra, Microstructure Evolution During Stainless Steel-Copper Vacuum Brazing with a Ag/Cu/Pd Filler Alloy: Effect of Nickel Plating, J. Mater. Eng. Perform., 2017, 26, p 1085–1100CrossRefGoogle Scholar
  12. 12.
    T. Suga, Y. Murai, T. Kobashi, K. Ueno, M. Shindo, K. Kanno, and K. Nakata, Laser Brazing of a Dissimilar Joint of Austenitic Stainless Steel and Pure Copper, Weld. Int., 2016, 30, p 166–174CrossRefGoogle Scholar
  13. 13.
    C. Tan, J. Yang, X. Zhao, K. Zhang, X. Song, B. Chen, L. Li, and J. Feng, Influence of Ni Coating on Interfacial Reactions and Mechanical Properties in Laser Welding-Brazing of Mg/Ti butt joint, J. Alloys Compd, 2018, 764, p 186–201CrossRefGoogle Scholar
  14. 14.
    M.M. Schwartz, Brazing, 2nd ed., ASM International, Materials Park, 2003Google Scholar
  15. 15.
    D.M. Jacobson and G. Humpston, Principles of Brazing, ASM International, Materials Park, 2005Google Scholar
  16. 16.
    O. Kozlova, R. Voytovych, M. Devismes, and N. Eustathopoulos, Wetting and Brazing of Stainless Steels by Copper-Silver Eutectic, Mater. Sci. Eng. A, 2008, 495, p 96–101CrossRefGoogle Scholar
  17. 17.
    N. Eustathopoulos, F. Hodaj, and O. Kozlova, The Wetting Process in Brazing, Advances in Brazing, Woodhead Publishing Ltd., Sawston, 2013, p 3–30Google Scholar
  18. 18.
    T. Venkateswaran, V. Xavier, D. Sivakumar, B. Pant, and G.D. Janaki Ram, Brazing of Stainless Steels Using Cu-Ag-Mn-Zn Braze Filler: Studies on Wettability, Mechanical Properties, and Microstructural Aspects, Mater. Des., 2017, 121, p 213–228CrossRefGoogle Scholar
  19. 19.
    A.A. McFayden, R.R. Kapoor, and T.W. Eagar, Effect of Second Phase Particles on Direct Brazing of Alumina Dispersion Hardened Copper, Weld. J., 1990, 69, p 399–407Google Scholar
  20. 20.
    Y. Wang, W. Teng, and Y. Yu, Electron Beam Brazing of Vanadium Alloy to Stainless with Electroplated Cu/Ag Coatings, China Weld., 2016, 25(3), p 9–15Google Scholar
  21. 21.
    ASM Handbook Vol. 5: Surface Engineering (ASM International, Materials Park, 1994)Google Scholar
  22. 22.
    V.N. Semenov, Special Features in Materials Used for Soldering Structure, Met. Sci. Heat Treat., 1999, 41, p 438–440CrossRefGoogle Scholar
  23. 23.
    V.N. Semenov, Regular Features of Hardening and Embrittlement of Soldered Steels and Alloys Heated by a Soldering Thermal Cycle, Met. Sci. Heat Treat., 1999, 41, p 441–445CrossRefGoogle Scholar
  24. 24.
    P.R. Subramanian and J.H. Perepezko, The Ag-Cu (Silver-Copper) System, J. Phase Equilib., 1993, 14, p 62–75CrossRefGoogle Scholar
  25. 25.
    X.J. Liu, F. Gao, C.P. Wang, and K. Ishida, Thermodynamic Assessments of the Ag-Ni Binary and Ag-Cu-Ni Ternary Systems, J. Electron. Mater., 2008, 37, p 210–217CrossRefGoogle Scholar
  26. 26.
    M. Venkatraman and J.P. Neumann, The Ag-Cr (Silver-Chromium) System, Alloy Phase Diagr., 1990, 11, p 263–265CrossRefGoogle Scholar
  27. 27.
    P.A. Korzhavyi, I.A. Abrikosov, and B. Johansson, Theoretical Investigation of Sulphur Solubility in Pure Copper and Dilute Copper-Base Alloy, Acta Mater., 1999, 47, p 1417–1424CrossRefGoogle Scholar
  28. 28.
    J.L. Van Noord and B.R. Stiegemeier, RP–2 Thermal Stability and Heat Transfer Investigation for Hydrocarbon Boost Engines, NASA/TM-2010-216917 (2010)Google Scholar

Copyright information

© ASM International 2019

Authors and Affiliations

  • T. Venkateswaran
    • 1
    • 2
    Email author
  • Vincent Xavier
    • 1
  • D. Sivakumar
    • 1
  • Bhanu Pant
    • 1
  • P. K. Jayan
    • 1
  • G. D. Janaki Ram
    • 2
  1. 1.Materials and Mechanical EntityVikram Sarabhai Space CentreTrivandrumIndia
  2. 2.Department of Metallurgical and Materials EngineeringIndian Institute of Technology MadrasChennaiIndia

Personalised recommendations