Accession Number : ADA262265
Title : Thermomechanical Fatigue Behavior of a Silicon Carbide Fiber-Reinforced Calcium Aluminosilicate Glass-Ceramic Matrix Composite.
Descriptive Note : Final rept. Aug 90-Dec 91,
Corporate Author : WRIGHT LAB WRIGHT-PATTERSON AFB OH
Personal Author(s) : Butkus, L M
Report Date : Aug 1992
Pagination or Media Count : 131
Abstract : Isothermal fatigue and in-phase thermomechanical fatigue (TMF) tests were performed on a unidirectional, continuous-fiber, Nicalon - reinforced calcium aluminosilicate glass-ceramic composite (10116, SiC/CAS-II). Monotonic tensile tests were performed; at 1100 deg. C and 100 MPa/sec to determine the material's ultimate strength and proportional limit. Isothermal fatigue tests at 100 deg. C employed two loading profiles, a triangular waveform with ramp times of 60 seconds, and a similar profile with a superimposed 60 second hold time at maximum stress. All fatigue tests used a maximum stress of 100 MPa, R = 0.1. TMF loading profiles were identical to the isothermal loading profiles, but the temperature was cycled between 500 and 1100 deg. C. All fatigued specimens reached run out (1000 cycles) and were tested in tension at 1100 deg. C immediately following the fatigue tests. Residual modulus, residual strength, cyclic stress-strain modulus, and strain accumulation were all examined as possible damage indicators. Strain accumulation allowed for the greatest distinction to be made among the type of tests performed. Fiber and matrix stress analyses and creep data for this material suggest that matrix creep is the primary source of damage for the fatigue loading histories investigated.
Descriptors : *STRESS ANALYSIS , *CERAMIC MATRIX COMPOSITES , *FATIGUE(MECHANICS) , TEST AND EVALUATION , THERMOMECHANICS , CALCIUM , FIBER REINFORCED COMPOSITES , CARBIDES , PHASE , RESIDUALS , SILICON CARBIDES , CREEP , TENSION , TIME , CYCLES , WAVEFORMS , HIGH TEMPERATURE , MATERIALS , TEMPERATURE , DAMAGE
Subject Categories : Ceramics, Refractories and Glass
Laminates and Composite Materials
Distribution Statement : APPROVED FOR PUBLIC RELEASE