The effect of additive particle size on the mechanical properties of sintered aluminium-copper alloys

Abstract

Fine additive particle sized often have advantageous sintering characteristics because the high surface area to volume ratio increases the driving force for sintering and because the powders are better distributed throughout the compact. Fine additive particles also leave smaller secondary pores in transient liquid phase sintering systems. Transient systems are sensitive to process variables such as heating rate because they control the volume of liquid which forms and the duration for which it exists. Additive particle sizes are therefore also likely to influence sintering in such systems. Indeed, it has recently been shown by microstructural examination that coarse additive particles can promote liquid formation and therefore enhance sintering in transient liquid phase systems. Here, the authors extend this work by determining the tensile properties as a function of additive particle size and heating rate in an aluminum alloy.