A study on quantitative formability assessment of rheological materials based on the microstructural characterization with a moderate control of the process

The semisolid forming (cleaner rheological forming) of aluminum alloys is a new net shape manufacturing method that incorporates elements of both forging and casting. It is characterized by the use of induction heating to reheat billets to the highest possible solid fraction in order to maximize the mechanical properties such as strength, wear resistance and elongation. It is necessary to develop tailored alloys specifically for cleaner rheological forming (CRF). The selection is basically from the entire range of cast and wrought aluminum alloys, although most of these alloys were optimized either for the casting or for the forging process. Nowadays, their formability evaluation in the semisolid state has rarely been investigated, and more essentially, it lacks a systematic theoretical base for dealing with unexpected behavior under the new and possibly extreme conditions encountered as we expand the limits of this criterion. So, the present article uniquely focused on an advanced description (advanced JK criteria) to evaluate the formability and castability of next-generation nonferrous materials such as cast and wrought aluminum alloys in the semisolid state based on the microstructural characteristics with an appropriate control of the process. Using the proposed criteria (advanced JK criteria) to evaluate the quantitative formability of cleaner rheological materials in the semisolid state shows that a nine-point alloy represents an optimal semisolid formability while a zero-point alloy is extremely unsuitable for CRF, confirming the validity of the proposed criteria.