Ceramic materials testing and fracture mechanics

Abstract

In general, metals deform by dislocation movement which is essentially a shearing process as the planes of atoms slip over each other. The process is referred to as “slip”. To be completely ductile there should be five systems in a crystal capable of independent slip movement (this is known as the von Mises criterion). Most FCC metals with a face-centred cubic lattice structure deform quite easily by slip, while other systems less so. If the criterion cannot be met, the behaviour is that of semi-brittle or brittle solids.