CERAMIC COMPONENT NONDESTRUCTIVE TESTING TECHNOLOGY

CERAMICS ARE BEING WIDELY CONSIDERED FOR REPLACEMENT OF METALS AND POLYMERS IN MANY ENGINEERING APPLICATIONS. THEIR CORROSION RESISTANCE, SMALL COEFFICIENTS OF THERMAL EXPANSION, LIGHT WEIGHT, LOW COST, EXCELLENT MECHANICAL PROPERTIES UNDER HEAVY STRESS, OUTSTANDING ELECTRICAL AND OPTICAL PROPERTIES, AND EXCEPTIONAL RESISTANCE TO HIGH TEMPERATURE, MAKE THEM VERY ATTRACTIVE IN STRUCTURAL, MICROELECTRONIC,AND BIOTECHNOLOGY AREAS. DESPITE THEIR DESIRABLE PROPERTIES, USE OF CERAMICS IS GREATLY RESTRICTED IN STRUCTURAL APPLICATIONS BECAUSE CERAMICS ARE BRITTLE AND THEIR PHYSICAL PROPERTIES ARE NONUNIFORM. TO ASSURE CERAMIC PRODUCT RELIABILITY, IT IS EXTREMELY IMPORTANT THAT THEY BE EXAMINED NONDESTRUCTIVELY. HIGH-FREQUENCY ULTRASONIC TECHNIQUES ARE PROPOSED TO DETERMINE GRAIN SIZE AND POROSITY, DETECT AND CHARACTERIZE SURFACE AND NEAR-SURFACE FLAWS INCLUDING CRACKS AND INCLUSIONS AND BULK DEFECTS. ULTRASONIC TECHNIQUES WILL BE EVALUATED ON SILICON NITRIDE, SILICA CARBIDE, AND ALUMINA CERAMICS.