INDENTATION INDUCED TESTING STUDIES ON OXIDE CERAMICS

Abstract

Ceramics are promising material having different properties in comparison to metals which have high melting point, high hardness and low fracture toughness. For ceramics fracture toughness is one of the major properties which hinder from their wide scale application of this material in various fields of human activities. For many years, the study of fracture toughness was the objective of scientific interest. The wide scale fracture toughness investigations were studied by variety of test method. In this dissertation work, the samples of ceramic particulate composite were made. Alumina (A1203) was taken as matrix material and silicon carbide (SiC) as particulate. The samples were prepared by standard ceramic processing route following solid state sintering at high temperature. The samples were characterized by Vickers indentation for their hardness measurement under different loading conditions. The samples were tested by three point bending for measurement of fracture toughness. The result shows the increase in fracture toughness in particulate composite. The improvement in fracture toughness was 1.45 times the HIP processed alumina. Then micro structural investigations were carried out and microstructural features attempted to correlate with the properties and results.