| 摘要 |
<p>A simple and economical method of forming a foundry mould for precision investment casting wherein the time period for allowing each applied refractory coating and stucco coating to set on a meltable mould former is substantially reduced by applying alternate coatings of immiscible, refractory particle binders to the mould former interspersed with stucco coatings, with at least one of the refractory particle binder coatings being in the form of a slurry containing refractory particles. This eliminates the necessity of having to allow one coating to set before the next one is applied. The alternate refractory particle binders used are a partially hydrolized, organo-silicon compound and an alcohol tolerant non-alkaline aqueous colloidal silica. Initially the mould former is coated with a refractory slurry having a suspended solids content in the range 30% to 50% by volume of the total slurry volume while the subsequent refractory slurries have a suspended solids content in the range 20% to 40% by volume of the total slurry volume.</p> |
