アルミニウム合金鋳造時にシェル中子から発生するガス圧

抄録

The relationship between the gas volume evolved from the cores furan resin bonded and phenolic resin bonded, and the gas pressure in a shell mold core during casting was investigated under the condition of equal gas volume evolution. Gas pressures at various portions of cores during casting an Al-7%Si-0.3%Mg alloy at 750°C was measured with a semiconductor pressure gauge newly developed. Shell mold cores 100mm in width, 150mm in length and 10, 15 and 20mm in thickness with a core print on its open side for degassing were used. The gas pressure is not in uniform distribution in a core and increases with the distance from the core print. The gas volumes evolved from both cores increase with increase in the amounts of resins. The gas pressure evolved from the furan coated sands is higher than that from the phenolic resin coated ones even under the condition of the same evolved gas volume. The difference in the gas pressure between two cores will be attributed to the difference in their initial gas evolution rate due to different decomposing temperatures rather than the evolved gas volume or the resin content.