アルミナ系水溶性鋳型に鋳造した鋳鉄鋳物の特性

抄録

  Dimensional accuracy and mechanical properties of solid and hollow cylindrical iron castings poured in alumina-base water soluble mold and silica-base CO₂ process mold were studied.
  Because the alumina-base mold has higher hot strength, there is very little wall movement, resulting in better dimensional accuracy and surface smoothness. Because the amount of thermal expansion of the alumina-base and silica-base mold materials are nearly equal at 750°C, castings poured in these molds have similar casting stress.
  The highest tensile strength of casting was obtained in the 30 mm diameter solid cylinder cast in the alumina-base mold, in which the calculated cooling rate was 7 degree/sec. The cooling power of the alumina-base mold is higher and the castings poured in this mold have directional dendrite structure and higher tensile strength. The level of hardness values and the uniformity of the values throughout the casting section were independent of the mold materials used.