Accession Number : ADA329853
Title : High Temperature Heterogeneous Materials
Descriptive Note : Final rept. 15 Jan 90-31 Aug 93
Corporate Author : NORTHWESTERN UNIV EVANSTON IL CENTER FOR QUALITY ENGINEERING AND FAILURE PREV ENTION
Personal Author(s) : Keer, Leon M. ; Faber, K. T. ; Moran, B. ; Weertman, J.
PDF Url : ADA329853
Report Date : 22 JUL 1994
Pagination or Media Count : 26
Abstract : Experimental and supporting analytical methodologies for the determination and assessment of the integrity of interfaces in composite materials at both room and high temperatures are presented. Experimental test techniques developed in the program are described and supporting analytical methods to assist in the determination of interface fracture toughness from experimental measurements are presented. The test techniques consist of the tensile test on a thin coated fiber and four point bend of a bimaterial bar and were chosen on the basis of their suitability for use at high temperatures. An experimental study of crack tip shielding/antishielding by impurities in alpha-silicon carbide is described. This investigation required the application of stress during high temperature (1873 K) anneals. A novel stress fixture, based on thermal expansion mismatch, was designed, constructed and utilized to achieve this in-situ stressing of the crack specimens at high temperatures.
Descriptors : *CRACKING(FRACTURING), *FIBER REINFORCED COMPOSITES, COMPUTER PROGRAMS, METHODOLOGY, TENSILE STRENGTH, FINITE ELEMENT ANALYSIS, THERMAL EXPANSION, SILICON CARBIDES, BINARY ALLOYS.
Subject Categories : Laminates and Composite Materials
Distribution Statement : APPROVED FOR PUBLIC RELEASE