Mechanical properties of powder injection moulded alumina

In this study rheolojical investigation were done using a binder: 65 wt% polyethlene glykol, 30 wt% polyethlene, 5 wt% stearic acid in composition. Fused alumina powder and above binder mixtures were injection molded by using various volume percents of alumina. Through these experiments critical solid loading for alumina powder was determined. Tensile and bending samples are produced by powder injection moulding of feedstock with 55 vol% alumina. Debinding and sintering of these molded samples were carried out. After sintering, in bending samples maximum 79 % teorical density, 13.74 % shrinkage and 133 MPa bending strength were determined. In tensile samples maximum 85 % teorical density, 14.17 % shrinkage and 64.17 MPa tensile strength were determined. Broken fracture surfaces of the samples were examined under scanning electron microscope. The optimum processing conditions for injection molding of alumina was determined.