Analysis of Brazing Effect on Hot Corrosion Behavior of a Nickel-Based Aerospace Superalloy
- 93 Downloads
The effects of brazing and use of composite powder mixture as interlayer material on hot corrosion resistance of brazed IN738 superalloy were studied. Brazing was observed to result in significant reduction in the hot corrosion resistance of the superalloy. However, application of composite powder mixture, which consists of additive superalloy powder, enhanced the hot corrosion resistance of brazed samples. It is also found that although the use of composite powder mixture increased hot corrosion resistance of brazed alloy, if the additive powder completely melts, which is possible during brazing, it can significantly reduce the hot corrosion resistance of the brazed joint. Elemental micro-segregation during solidification of the joint with completely melted powder mixture produces chromium-depleted zones and consequently reduces hot corrosion resistance, since a uniform distribution and adequate chromium concentration are necessary to combat hot corrosion. This has not been previously reported in the literature and it is crucial to the use of composite powder mixture for enhancing the properties of brazed superalloys.
The authors gratefully acknowledge financial support from NSERC of Canada.
- 1.W. F. Smith: Structure and properties of engineering alloys, McGraw-Hill book company, New York, 1981.Google Scholar
- 2.W. Miglietti: Proceedings of the 4th International Brazing and Soldering Conference, Orlando, FL, 2009.Google Scholar
- 3.M Chunwei, S Kun, Y Zhishui, and X Peiquan: Acta Metall. Sin. (Engl. lett.), 2011, vol. 24, pp. 205–212.Google Scholar
- 4.B. Jahnke and J. Demny: Metall. Ceram. Prot. Coat., 1983, vol. 110, pp. 225-235.Google Scholar
- 8.A. Ghoneim: PhD Thesis, 2011, University of Manitoba, Winnipeg, Manitoba.Google Scholar
- 9.J.F. Hunedy: Master’s Thesis, 2013, University of Manitoba, Winnipeg, Manitoba.Google Scholar
- 21.M.N. Task: Master’s Thesis, 2010, University of Pittsburgh, Pittsburgh, Pennsylvania.Google Scholar
- 25.C. T. Sims and W. C. Hagel: The Superalloys, John Wiley & Sons,New York, 1972.Google Scholar