IBM Corporation, General Technology Division, Endicott, N.Y.
Pages: 12 Published: Jan 1984
The purpose of this paper is to expand the understanding of 96% alumina ceramic breakage in metalized ceramic (MC) processing. By observing the location of cracks and studying the fractured surfaces, it is possible to determine the origin of the fracture, the type of fracture, and the relative stresses that caused the fracture. Cracks were observed by the use of dye penetrants, and fracture surface details were enhanced by spraying with collodial graphite. Scanning electron microscopy (SEM) photomicrographs were used to distinguish between intergranular and transgranular fractures.
Breakage that occurs during MC processing includes impact from substrate handling, bending during the pinning operation, and thermal effects from tinning. These cracks and fractured surfaces were compared with substrate damage caused by known types of applied stresses. Samples from impact testing, flexural strength measurements, pinning, and thermal shock studies were used. Impact breakage occurs primarily in corner cracks and chips. Breakage from bending occurs during pinning and flexure testing. The fractured surfaces show concave crack front profiles originating from the tensile surface. Thermal shock fractures caused by tinning produce smooth and wavy fractured surfaces.
ceramic breakage, cracks, fractured surfaces, impact shock, bending breakage, thermal shock, ceramic substrate, graphite coating, pinning, tinning
Paper ID: STP37112S