焼結とＨＩＰによる鉄銅ち密積層材料の延性と靭性

Abstract

The die cavity, 40 mm in diameter, was filled step by step with electrolytic iron and copper powders alternately. Then, the layered columns of the powders were pressed, sintered and HIPed to solid laminated composites of 2-16 layers.At -196°C, the load/deflection curves and the ultimate tensile strength of the composites varied with the number of layers. In some of the 8 and 16 layer-composites, the iron layers were fractured continually into shorter and shorter lengths at -196°C, leading to somewhat larger elongation of the composites.In the crack divider type of impact specimens, a pair of shear lips was formed at a low temperature on the fracture surface of each iron layer constructing a composite. As the number of layers was increased, the shear lips amounted to a certain area of ductile fracture and resulted in a decrease of the ductile-brittle transition temperature.In the crack arrester specimens, the extent of the delamination increased as the number of layers was decreased. This prevented the cracking in the next iron layer before delamination took place, and resulted in a rather high impact strength.