Development of an inorganic core binder system for multiple applications under varying foundry conditions

摘要

Inorganic core binders and their applications are increasing in frequency as foundries explore their potential due to improved environmental awareness. From foundry to foundry each and every application is different. It is clear that binder recipes must be account specific and thus designed accordingly. Specific knowledge of multiple processes and process requirements allows for the development of product specific binder solutions for any given aspect; be it necessary for high strength, moisture resistance, flowability of prepared sand admixtures, de-coring or reclaimability. For the customer all these parameters must be considered when selecting a binder. Development of binder recipes and combinations with additives has allowed suppliers to meet the above process requirements. Without this development modern inorganic binders would not exist. During development of inorganic binder systems it is necessary to conduct metallurgical investigations of castings for soundness. This is a result of inorganic binders promoting different solidification characteristics of an alloy compared to that of organic binder systems. The pouring process itself and the thermal gradients this imposes on a mould and core design should not be neglected whilst using environmentally friendly inorganic binder systems. It is therefore critical that thermal gradients produced in a mould and core during pouring and solidification are understood allowing optimization of the gating and feeder technology utilized. This paper represents progress made through intensive research and practical examples when the AWB inorganic core binder system was introduced into the process at a low pressure die caster for the production of brass faucets