硅酸乙酯模壳低温焙烧工艺的研究

Study on the Technology of Sintering Shell Mold at Low Temperature

研究了焙烧温度对硅酸乙酯模壳性能的影响,分析了影响模壳性能的因素,并通过在制壳涂料中加入附加物,降低了模壳的发气量,提高了透气率,使700℃焙烧的模壳性能近似于850～950℃焙烧的模壳性能,并对附加物低温焙烧机理及附加物的分解产物进行了分析研究。浇注实验表明,采用低温焙烧的模壳,可获得表面光洁(Ra=3.4～6.3μm),尺寸精确(10±0.05mm),无气孔的熔模铸件。

Synopsis: In this paper, the influence of sintering temperature on the propertis of shell mold using ethyl silileate as binder is discussed and factors affecting properties of shell mold are analysed. The properties of shell mold sinterea at 700℃ are approximately similar to that under 850～950℃ because the gas evolution rate of shell is reduced and its gas permeability is increased by putting additions into slurry which is used for making shell mold. Then the mechanism of sintering at low temperature is put forward. The pouring experiment shows that aluminium precision castings without gas holes and smooth surface and precise size are obtained by using shells sintered at low temperature.