000202950 001__ 202950
000202950 005__ 20180913062817.0
000202950 0247_ $$2doi$$a10.1016/s1359-6454(96)00412-0
000202950 022__ $$a1359-6454
000202950 037__ $$aARTICLE
000202950 245__ $$aTime-dependent failure in fiber-reinforced composites by matrix and interface shear creep
000202950 260__ $$c1997
000202950 269__ $$a1997
000202950 336__ $$aJournal Articles
000202950 520__ $$aThe inelastic response of fiber-reinforced ceramic and metal matrix composites under fixed load at elevated temperature is due to the complementary effects of creep and damage in the constituents. After matrix cracking or tensile creep relaxation in a short time, subsequent deformation and failure are driven by shear stress relaxation in the matrix and at the fiber-matrix interface around broken fibers. The shear creep causes stress redistribution to unfailed fibers, causing Further fiber breakage and shear relaxation, culminating in abrupt failure of the composite. This sequence of events is modeled both analytically and numerically within the Global Load Sharing (GLS) approximation previously utilized for quasi-static loading. Analytically, a unit cell model is used to obtain simple closed-form relationships For the time-dependent relaxation of the shear at the interface. This relaxing shear stress is then incorporated into a simulation model which follows the evolution of slip and fiber damage up to failure. The slip lengths and failure times are predicted vs matrix creep exponent n, fiber Weibull modulus in, applied load and, interestingly, physical specimen length. An analytic model for failure shows good agreement with the simulation results and so can be used for qualitative estimates of lifetime. Application to Ti-MMCs is discussed. (C) 1997 Acta Metallurgica Inc.
000202950 6531_ $$arecovery behavior
000202950 6531_ $$astrength
000202950 6531_ $$atensile creep
000202950 700__ $$aIyengar, N.
000202950 700__ $$0246474$$aCurtin, W. A.$$g211624
000202950 773__ $$j45$$q3419-3429$$tActa Materialia
000202950 909C0 $$0252513$$pLAMMM$$xU12614
000202950 909CO $$ooai:infoscience.tind.io:202950$$pSTI$$particle
000202950 937__ $$aEPFL-ARTICLE-202950
000202950 970__ $$aiyengar_time-dependent_1997-1/LAMMM
000202950 973__ $$aOTHER$$rREVIEWED$$sPUBLISHED
000202950 980__ $$aARTICLE