Microstructural Study of Aluminium Alloy A390 After Milling Process

Aluminium alloy has been receiving a lot of attention from the automotive industry due to its lightweight characteristic that can lead to a reduction in fuel consumption. It is a well-known fact that light components made from aluminium alloy are more cost effective when it comes to the manufacture of block engines and pistons than those made from steel. Among the aluminium alloy fabrications that have grabbed the attention of researchers are alloy mould casting with 9.5 wt.% Si (383), alloy sand mining with 18.5 wt.% Si (A390) and alloy spraying with 25 wt.% Si (Al-25Si). Alloy 390 is suitable for replacing metal cast components due to its higher silicon content, which can help to reduce heat expansion and has good corrosion characteristics. This research presents an observation of the microstructure of aluminium alloys after the machining process. The cutting parameters used were a cutting speed of 250-350 mm/min, feed rate of 0.02-0.04 mm/tooth, and radial width of cut of 12.5 mm-25 mm. while the depth of cut was kept constant at 0.3 mm. The machining process was carried out under dry and cryogenic conditions. The resultant observation of the microstructure showed the effects of the heat generated during the cutting process at a cutting speed of 350 m/min, feed rate of 0.02 mm/tooth and radial width of cut of 12.5 mm under dry conditions with a worn cutting tool, while for the other cutting parameters, no effects from the heat were observed. No changes in the microstructure were observed through the use of the stated cutting parameters. This showed that the temperature generated during the cutting process was low, and thus, did not cause any changes to the microstructure within the range of the studied cutting parameters.