Copper and silicon, principal alloying elements of copper-silumin, seem to have effects on mechanical properties and machinability of the copper-silumin.
This paper describes the dry orthogonal cutting tests performed on the copper-silumin containing05.0% of copper and 4.512.0% of silicon; and effects of copper and silicon contents on chip formation, built-up edge, shearing angle, friction angle, etc. are discussed.
The results obtained were as follows:
In the alloys containing copper, the chip formation was almost equal to the flowing type with the formation of built-up edge; but in the alloys containing no copper, it was close to a tearing or shearing type and the chip thickness was extremely increased according to the plastic flow of materials. When copper content was more than 3.0%, the built-up edge and cutting resistance became relatively smaller and no differences were observed in cutting mechanism. In the alloys containing 4.5% of silicon, shearing angles were small, and the cutting efficiency was especially low when no copper was contained. However, when silicon content was 8.012.0%, no differences were observed in cutting mechanism.
The hard acicular or tabular particles of silicon, which had been ruptured by cutting action, were uniformly distributed in the built-up edge. Such a behavior of the particles would contribute to increase the hardness of built-up edges.
