Ultra-high speed machining of A356-T6 aluminum alloy for automotive applications

Advanced manufacturing technology of high silicon aluminium alloys is one of the manufacturing processes in need of new developments to obtain the required improvements for the new generation of vehicles. During ultra high speed machining of aluminium alloys, the optimum machining parameters and tool geometry are controlled by the finished machined workpiece/part surface integrity, burr formation, and part distortion. For the research objectives presented in this paper a dual approach was applied, covering both experimental and theoretical (modeling) work. High speed machining, above 5000 m/min, has been used. From experimental analysis, the most important elements regarding tool life and wear mechanisms are workpiece material microstructure and inhomogenities, non-metallic inclusions, and silicon content. Finite element analysis showed that when the flank wear was > 0.2 mm, the tensile residual stress magnitude and penetrated depth into the workpiece material increases, affecting the fatigue performance. The burr height increased with less positive rake angle and higher flank wear length.