Prediction of knit line formations in complex high pressure die cast magnesium alloy components

Abstract

This work investigates the formation of as cast defects in knit line regions and their effects on local mechanical properties in a thin walled high pressure die cast AM60B magnesium alloy component. The defect distributions and the tensile and bending properties of specimens cut from knit line and other regions are compared. Numerical simulations of the mould filling process, computed X-ray tomography experiments and reports from the literature are used to formulate an initial explanation for the occurrence of metal front dispersion in knit line regions. This is an initial study for a future project investigating knit line formation and process-structure correlations in cast magnesium alloys.