Properties of sialon ceramics evaluated by means of multifractal, surface stereometry and quantitative fractography techniques

Resistance to brittle cracking is one of the most important functional properties of sialon ceramics. For this reason, the fullest possible characterization of the decohesion processes occurring in this material is required. A quantitative description of fracture surfaces and profiles formed in a three-point bending test was made using three research methods and techniques. The aim was to provide a comprehensive description of typically brittle fracture morphologies as well as to determine a set of quantitative fractographic parameters, which would enable characterizing the fracture by means of a stereometric method, by multifractal analysis and a fractograpic method. Using the parameter Sdr determined via the surface stereometry method, the fracture area development coefficient RS was calculated. Analysis of the results indicates a proportional relation between this parameter and the bending strength of sialon ceramics.