(1) Aiming at the common shrinkage and porosity defects in semi-solid die-casting thick wall products, the microstructure analysis and mechanical properties test were used to characterize the defects. The influencing factors of the defects were determined by design experiments. Finally, the influence rules of different production process parameters on the defects were proposed.
(2) Aiming at the common solid-liquid segregation defects in semi-solid die-casting thick wall products, the microstructure analysis and mechanical properties test were used to characterize the defects. The influencing factors of the defects were determined by design experiments. Finally, the influence rules of different production process parameters on the defects were proposed.
(3) The effect of solid-liquid segregation defect on mechanical properties in semi-solid die casting and the influence of different process parameters on mechanical properties were studied.
Due to the lack of systematic defects research in semi-solid die casting, in order to solve the defects of products in the actual production process, the appropriate die-casting process is usually selected by trial and error method or by referring to liquid die-casting, which ultimately makes the research and development cycle too long and the research and development cost is too high. These consequences directly affect the further promotion of semi-solid die-casting technology.
(1) Two kinds of defects in semi-solid die-casting thick wall castings can be predicted effectively;
(2) To guide and control two kinds of defects in thick wall semi-solid die casting;
(3) Promote the development of semi-solid die casting thick wall products.