Effects of Na and P on machinability of JIS AC8A aluminum alloy

Abstract

Turning test were conducted on JIS ACBA aluminum alloy casting to study the effects of Na and P on its machinability.The results obtained were summarized as follows :(1) The cutting resistance of the specimen treated by Na was slightly higher than that of the specimen treated by P.(2) The roughness of the finished surface was nearly under the same conditions between the both specimens treated by Na and P. Remarkably irregular surface was found in the range of low cutting speed owing to the adhesion of built-up edge on the tool rake face and the rising of machined surface during cutting. However, the built-up edge disappeared with the increase of cutting speed and the roughness of machined surface approximated to the theoretical roughness.(3) The chip forms and chip treatments were nearly under the same conditions between the both specimens treated by Na and P.(4) The tool life for the specimen treated by P was much shorter than that for the specimen treated by Na with the increase of cutting speed.