Fracture path prediction of diamond segment in a marble cutting disc

摘要

This study investigates the fracture path behaviour of diamond segments that have been brazed on a marble cutting disc. The segments are braze-joined using the oxy-gas welding technique. The micro-structure of the brazing zone and the disc were investigated using standard metallographic techniques and scanning electron microscope (SEM). Additionally, we used numerical modelling to study crack growth at the welding zone. Two dimensional linear elastic fracture mechanics principles were used to analyze propagation behaviour of the crack. Stress intensity factors were calculated using displacement correlation method. It was deduced from the SEM analysis of the fractured segment surface that the fracture occurred in the diamond segment due to stress concentration near the sharp corners of the diamond particles that are embedded into the matrix. The existence of such sharp artefacts within the matrix leads to the formation of cracks.