The Response of Two Al-Si-Mg Castings to an Integrated HIP and Heat Treat Process

The temperature range used for HIP processing of cast aluminum parts is also appropriate for solution heat treatment. Integration of these two processes should decrease processing time, energy consumption, and processing cost. In this study, Al-Si-Mg castings were subjected to a combined HIP and T6 heat treatment. The properties and microstructure of these castings were compared to parts processed using conventional methods. Apparent differences in the oxide concentration provided insight into the effect of oxide inclusions on HIP response. Results indicate that fatigue life is increased using an integrated HIP/heat treat process, however, oxide contamination can negate this improvement.