DUST-FREE INVESTMENT MATERIAL FOR PRECISION CASTING AND PROCESS FOR THE PREPARATION OF SUCH INVESTMENT MATERIALS

摘要

Dust-free investment materials for producing precision castings consisting of water-soluble phosphates, magnesium oxide and silicon dioxide are obtained when the investment material is divided into two components a and b, where component a contains all the magnesium oxide, where appropriate a part of the silicon dioxide and, if silicon dioxide is present, 0.4 to 6% by weight of a hydrophilic organic solvent, and component b contains the phosphate, the remainder of the silicon dioxide and at least 0.5% by weight of water.