| abstract |
No-bake inorganic binder compositions for binding particulate material and methods for curing such inorganic binders. The inorganic binder compositions are composed of silicate and phosphate components. The no-bake compositions further contain curing catalyst such as a catalyst selected from the group consisting of aliphatic carbonates, cyclic alkylene carbonates, aliphatic carboxylic acid esters, cyclic carboxylic acid esters, phosphate esters and mixtures thereof. The composition produces a binder having the advantageous strength properties of a silicate binder system with the water breakdown properties of a phosphate binder system. Thus, relative to an all-silicate binder system, the present invention has improved mechanical shakeout and improved water collapsibility. Also, relative to conventional all-phosphate binder system, the present invention has superior hot strength, i.e., the foundry cores and molds do not soften at elevated temperatures. Methods of making and using the binder compositions and the resulting products are of particular interest to the foundry art. |