Characterization of the hot deformation behavior of a Al-Si alloy using processing maps

The compression tests of solution treatment ZL109 alloy have been performed in the compression temperature range from 250 degrees C to 450 degrees C and the strain rate range from 0.0005s(-1) to 0.5s(-1). A processing map has been developed on the basis of flow stress data obtained as a function of temperature and strain rate, which revealed two domains of hot working for the alloy: one is situated at temperature between 270 degrees C and 340 degrees C with strain rate between 0.05s(-1) and 0.5s(-1), the other is situated at the temperature between 380 degrees C and 450 degrees C with strain rate between 0.0005s(-1) and 0.004s(-1). Combining with the processing map, the optimum parameters of hot working for ZL109 alloy are that 300 degrees C/0.5s(-1) and 450 degrees C/0.0005s(-1), respectively. Microstructure observations indicated that DRX occurred in both these domains. The instable zones, i. e., adiabatic shear bands formation, wedge cracking, were also identified in the processing map and microstructural examination was performed for validation.