Abstract
In this study, the properties of metal castings obtained from commercial gypsum-bonded investments for the quick heating method were investigated.Three gypsum-bonded investments for the quick-heating method and two conventional gypsum-bonded investments were employed;dimensional accuracy, surface roughness, surface hardness and tensile properties of Ag-Pd-Cu-Au alloy castings obtained from these investments were examined.No casting fins were observed on the casting surfaces.Dimensional accuracies of the castings were varied with the investment used.Surface roughness values were similar except for one conventional investment.Micro-vickers hardness numbers of the castings obtained from the quick-heating investment were slightly smaller than those from the conventional investments.Tensile properties, such as tensile strength, proof strength, elastic modulus and elongation showed no differences among the castings.These findings suggested that there were no obvious differences between the properties except for the casting accuracy of the castings obtained from the quick-heating and those from the conventional investments.
