To investigate the preparation of cristobalite and the influence of cristobalite on properties of the phosphate-bonded investment,the authors respectively put quarts into muffle stove and heat to 1 400, 1 500,1 600,1 650 ℃, and keep for 3 hours.

A review & outlook for the production of feedgrade phosphates;

The situation of market and production of feedgrade dicalcium phosphate in China is introduced, the basic causes for limiting the development of feedgrade dicalcium phosphate are analysed, the existed problems are put forward, and some suggestions on the development of feedgrade phosphate industry are given.

The development trend of feed-grade phosphate for MDCP;