CASTING DEVELOPMENT BY COMPUTER MODELING

THIS PROJECT IS DESIGNED TO PROVIDE A TOOL TO IMPROVE THE QUALITY OF CASTINGS PRIMARILY BY CONTROL OF MICROSHRINKAGE. IT WILL HAVE TWO OBJECTIVES; (A) IMPROVE THE QUALITY OF COMPONENTS CURRENTLY PRODUCED BY CASTING, AND (B) FACILITATE THE APPLICATION OF CASTING METHODS TO OTHER COMPONENTS THUS REDUCING COSTS. WE PROPOSE TO ACHIEVE THESE OBJECTIVES BY DEVELOPING A COMPUTER MODEL FOR THE CASTING PROCESS WHICH PREDICTS MICROPOROSITY FORMATION. THE MAIN TASK ADDRESSED IN THIS PROPOSAL IS THE DETAILED TREATMENT OF THE METALLURGICAL FEATURES OF SOLIDIFICATION. THE MODEL WILL HAVE THE ABILITY TO PREDICT THE DEPTH OF THE FREEZING INTERFACE, THE FINENESS OF THE GROWING DENDRITES, AND THE PARTITIONING OF DISSOLVED GAS, AND WILL COMPUTE FLUID FLOW NEAR THE ADVANCING SOLID-LIQUID INTERFACE. HENCE, WE WILL PREDICT THE POSITION AND SIZE OF VOIDS FORMED DURING FREEZING. THE RESULTS WILL BE COMPARED WITH OBSERVATIONS. BY ADDING A MORE DETAILED HEAT FLOW TREATMENT (IN TASK III BUT MAINLY IN PHASE II), COUPLED WITH PRACTICAL EXPERIENCE AND SOME EXPERIMENTATION THE MODEL COULD BE READILY EXTENDED TO MORE COMPLEX CASTIG SHAPES.