This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Repair of Trailing Edge of C1023 NGVs by a Gouge-and-Braze Technique
Annotation ability available
Sector:
Language:
English
Abstract
A gouge-and-braze technique has been investigated as an alternative to repair cracks sustained at the trailing edges of C1023 nozzle guide vanes. Slots of four different widths, namely, 0.3, 0.6, 0.9 and 1.2 mm, were gouged at the trailing edge, either by a low-speed diamond- impregnated saw or by electro-discharge machining (EDM), to simulate the crack gouging process. The slots were then blasted with glass beads, SiC particles or nickel powder. Then, they were pre-packed with braze mixes, with an excess of braze mixes deposited on top of the slots, and brazed in vacuum at high temperature. A few slots were also similarly brazed but in the as-gouged conditions. The results show that the as-saw cut slots can be brazed readily but it is not so for the as-EDM slots. Blasting by glass beads, SiC particles or nickel powder is effective in improving the wetting characteristics of slot surfaces. The results further show that slots wider than 0.3 mm can only be successfully brazed with braze mixes containing 30 to 50% of gap filler. The advantages and limitations of using filler metal alone instead of braze mixes as excess filler deposit on top of the slots are also investigated.
Recommended Content
| Technical Paper | Turbine Component Restoration by Diffusion Brazing |
| Technical Paper | P/M Valve Seat Inserts: Air Quenching and Characterization |
| Ground Vehicle Standard | Leakage Testing |
Authors
Citation
Lim, L., Sivashanker, S., and Tung, S., "Repair of Trailing Edge of C1023 NGVs by a Gouge-and-Braze Technique," SAE Technical Paper 940008, 1994, https://doi.org/10.4271/940008.Also In
References
- Lindblom, Y. Materials Science and Technology 1 8 1985 636 641
- Mobley, P.R. Hoppin G.S. III, Welding Journal 40 6 1961 610 617
- Zhuang, H. Chen, J. Lugscheider, E. Welding in the World 24 9/10 1986 200 208
- Lugscheider, E. Schittny, Th. Brazing and Soldering 14 Spring 1988 27 29
- Johnson, R. Welding Journal 60 10 1981 185s 193s
- Lugscheider, E. Krappitz, H. Welding Journal 65 10 1986 261s 267s
- Gove, K.B. Metals and Materials 5 6 1989 341 344
- van Esch Hans Marijnissen G. Turbomachiner International Sept. 1986 29 32
- Lim, L.C. Lee, L.C. Wong, Y.S. Lu, H.H. Materials Science and Technology 7 3 1991 239 248
- Tung, S.K. Lim, L.C. “An Examination of Void Formation in Wide Gap Brazing with Pre-Packs of Nickel-Base Braze Mixes” Materials Science and Technology - in print