| 摘要 |
PURPOSE:To produce a metal-based composite material excellent in strength and thermal stability at a low cost by incorporating a potassium hexatitanate fiber having a specified form and impurity composition as the reinforcement into a light metal by high-pressure casting. CONSTITUTION:The short fibers of potassium hexatitanate having 8-30mum average length, 0.2-0.7mum average diameter and 2-4m<2>/g specific surface area and wherein the molar ratio of the Al2O3 to Nb2O3 as impurities is controlled to >0.6 and the total amt. of the impurities other than Al and Nb to <1.0% are mixed with an org. binder, and the mixture is sintered at 800-1100 deg.C to obtain a preform. The preform is arranged in a metallic mold, the molten alloy of light metals such as Al and Mg is injected into the mold, and a light metal- based composite material contg. 5-40vol.% of the fiber as the reinforcement is produced by high-pressure casting. Consequently, since the fiber is lower in cost than other ceramic whiskers, the composite material excellent in strength and thermal stability is obtained at a low cost. |
