W. Kasprzak, J. Sokolowski, University of Windsor, Windsor, ON, Canada; H. Yamagata, H. Kurita, Yamaha Motor, Iwata, Japan
Experimental results pertaining to development of the energy efficient heat treatment processes for Al-Si automotive vacuum High Pressure Die Casting (HPDC) components are presented. Precision high frequency induction heating combined with computer controlled processing (including the compressed gas/water quenching system) was used for laboratory simulation of the complex heat treatment operations like the multi-stage Solution Treatment, Artificial Aging and Interrupted Quenching, etc. In addition, the temperature vs. time curves and their derivatives were used for quantification of the process parameters. The experimental results showed that the duration of the conventional T6 heat treatment can be reduced by 50% without compromising hardness. This was accomplished by carrying out a short 30 minutes Solution Treatment above the incipient melting temperature (i.e., 510oC) and integration of the Solution Treatment, Quenching and Artificial Aging operations. Laboratory simulation of the T5 heat treatment consisted of casting water quenching after de-molding operation followed by Artificial Aging at 200oC for 2 hours revealed the possibility for further process time reduction by an additional 50%.
