Machinability of aluminum alloys

As aluminum alloys have high strength-to-weight ratio, they are used for many automobile parts. Aluminum alloys are generally machined for the improvement of the dimensional accuracy. In finish cutting of the conventional aluminum alloy such as a 6061 aluminum alloy, the continuous chips have a bad influence on the machining operation. In this study, in order to clarify the influence of Si contents in the aluminum alloys on cutting characteristics, five kinds of the aluminum alloys, which had the different Si contents, were turned. The tool materials used were high speed steel and cemented carbide. In turning of the aluminum alloys, the chip configuration, cutting forces and tool wear were experimentally investigated. The main results obtained are as follows: (1) The inferior feed rate limit, which can be obtained the desirable chip configurations for the chip control, decreased with the increase of the Si contents of the aluminum alloys. (2) In case of the high speed steel tool, the tool wear increased with the increase of the Si contents. However, in case of the cemented carbide tool, there was little influence of the Si contents on the tool wear.