Obstacles to High Temperature Cyclic Structural Durability of Continuous-Fiber MMCs
Increases in high temperature cyclic structural durability are being sought constantly. Materials for the next generations of machines must be designed to resist higher stresses and strains, and for elevated temperature use, must also resist time-dependent, thermally-activated damage mechanisms such as creep and oxidation. If mission usage involves temperature excursions, thermal-gradient induced stresses and strains will be superimposed on mechanical stresses and strains. The combined strains adversely interact with environmental attack mechanisms. The end result is a complex cyclic variation of strain, stress and temperature, with time-dependent creep, diffusion, oxidation, etc.
KeywordsStrain Range Continuous Fiber Thermal Expansion Mismatch Thermomechanical Fatigue Tungsten Fiber
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- C.W.Richards, Engineering Materials Science, Wadsworth, San Francisco, 1961.Google Scholar
- G.R.Halford, B.A. Lerch, J.F. Saltsman and V.K. Arya, ASTM STP 1186, 1993, p. 176.Google Scholar
- B.A.Lerch and G.R. Halford, Accepted for Materials Science and Engineering, 1995.Google Scholar
- G.R.Halford, Thermal Stresses II, Chapter 6, North-Holland, Amsterdam, pp. 329–428.Google Scholar
- D.W.Petrasek, NASA-Lewis Res. Center, Cleveland, OH, Personal Communication.Google Scholar
- M.G.Castelli and J.Gayda, DE-Vol. 55, ASME, 1993, pp 213–221.Google Scholar