Aluminium and its alloys have been widely used in the automotive industry for some time and A356 is one of the most popular aluminium alloys today in the sector. It contains approximately 7 wt.% Si and 0.3 wt.% Mg. Due to the defects that may be present in the cast parts, expected mechanical properties may not be reached and this alloy may perform in service under its potential. In a low pressure die casting, several precautions have to be taken in order to produce high quality and defect-free castings. Temperature of casting and the schemical composition of the melt is recorded continuously. Die temperature, pressure levels and their durations are optimized; degassing and fluxing operations are performed. Yet, regardless of the precautions, there could still be rejected parts. It is becoming clear that a good quality raw material is one of the most underrated points of the industry and that the starting material has a great effect on the final product and it should be taken in to account more seriously. Therefore, regarding the first rule of Campbell’s 10 Rules of Casting, in this study, the quality of the starting material of supply chains for a wheel manufacturer was investigated. Chemical compositions were compared, fluidity tests, mechanical tests and bifilm indexes of these various sources and ingots were measured and a final quality index was proposed to create a reference for the quantification of quality of supplier’s ingots. This new index was compared with the rejection rates.
Aluminium and its alloys are the most commonly used alloys in the transportation sector due to their high lightness and strength ratio. The higher corrosion resistance increases the reason why this alloy is preferred. In order to increase the strength values to the desired levels, aluminium alloys are subjected to grain refining with Ti, solution hardening with Mg and Cu and microstructural modifications with Sr. In this study, the relationship between Ag addition to Al-Cu alloy, mould filling ability with Sr addition to Al-Si alloys were investigated. In addition to the traditional spiral tests, newly developed 8-spoke, which is named as octopus design, was used to characterise the fluidity. Ag addition in the Al-Cu alloy (201) has no effect on fluidity particularly in spiral test but it has been observed to increase the strength by 50-80 MPa. On the other hand, high fluidity and strengths up to 350 MPa were achieved by A380 alloy.