ASSESSMENT OF THE STATE OF PRECIPITATION IN ALUMINUM CASTING A356.2 ALLOY USING NONDESTRUCTIVE MICROSTRUCTURE ELECTRONIC PROPERTY MEASUREMENTS

Application of nondestructive electronic property measurements to assess the strengthening of Mg2Si precipitates in aluminum A356.2 casting has been demonstrated. The results indicated the evolution of precipitation phase through over aging with increased cooling time or thickness of the cast part. The classical optimum precipitation behavior has been characterized and verified with thermal analysis, thermoelectric power, low frequency impedance, and micro hardness measurements. A proposed practice to use nondestructive electronic property measurement tools to assess aluminum casting for acceptable mechanical properties after mold shake out is presented.