Thermodynamic calculation as a tool for thixoforming alloy and process development

A two-stage thermodynamic calculation is proposed as a tool to analyze the alloy related aspects in semisolid forming processes. The two process stages are identified as: (i) equilibration in semisolid state and (ii) subsequent fast solidification of the material. For the example of Mg-Al-Zn-Ca alloys the results and limitations of this modeling approach are given. The wealth of information provided, such as process temperature and sensitivity, freezing ranges and the detailed constitution of the processed material, is suggested to assist in alloy development.