PROCESS FOR THE PREPARATION OF SHELL MOULDS FOR METAL CASTINGS

摘要

The present invention relates to the preparation of shell moulds for metal casting. The shell moulds are prepared from refractory materials which are bound by means of a binder based on a partially hydrolysed, partially condensed silicic acid ester. Alternating with this a slip of binder and refractory material as well as particulate refractory material is applied to the pattern to be copied. According to the invention, the particulate refractory material contains the hardener for the binder. The procedure according to the invention makes possible the dimensionally faithful reproduction of even large patterns, with which the slip employed can be stored away even over a long period, without reduction in its effect.