Investigation of the productability of the AlSi9Cu3 alloy part produced by high-pressure casting method using semi-solid casting methods

Liquid metal high pressure casting (HPDC) is the most popular process for casting aluminum alloys due to the unique characteristics of high productivity and low production cost. However, the Al alloys produced by HPDC contain numerous of porosity and oxides due to gas entrapment during mold filling. Such porosities can severely impair mechanical properties, inhibiting further property development through heat treatment and welding. Today, the production of many parts for the automotive industry is carried out by aluminum casting method. Significant lightening has been achieved, for example, by substituting aluminum alloy for engine blocks instead of cast iron. It is not possible to reach the elongation-toughness values ​​expected from some safety-critical parts by pressure casting. One of the promising technologies for producing high integrity components is semi-solid metal (SSM) processes, including thixoforming and reoforming. The number of aluminum alloy casting parts that can replace iron casting parts is increasing day by day. In addition to this increase, the mechanical properties and metallographic properties expected from aluminum alloy casting parts increase. In this project, the research of semi-solid casting methods and the development of the process that can provide mechanical and metallographic improvement are discussed. Semi-solid processes of alloys have been talked about for many years. Different semi-solid casting methods for aluminum alloys have proven to be a niche technology with limited applications, particularly in the automotive and consumer product markets, along with some successful industrial applications. However, despite the strong competition from traditional casting and especially permanent die casting processes and the emergence of additive manufacturing, there is a recovery in demand due to the high quality properties of semi-solid alloys. In addition to the product quality, the main industry has an intense demand for semi-solid casting for the parts that are already produced by low pressure casting and reached the specifications of the main industry companies with T6 heat treatment. The existence of such a trend has created the prediction that this trend will increase on a global scale. The most important aim of the project is to obtain the globular grain structure and to determine the process parameters in the Rapid Slurry Casting (RSF) and Cooling Slope Casting methods. In addition, this project is carried out as the TEYDEB 1501 project of Döktaş company, and another aim is to provide the company with semi-solid casting capabilities.