Abstract
The plastically deformed layer induced by drill cutting of 4650 sintered steels using prealloyed and elemental powders were investigated in this study. The microstructures, pore elimination and microhardness on the surface of cut holes were determined to evaluate the surface deformed layer thickness. The results obtained are summarized as follows;
1. The internal pore area tends to increase from the drill hole surface toward inside.
2. The metal flow is observed at the drill hole surface, but the boundary is not so clear that the thickness of plastically deformed layer cannot be measured.
3. Microhardness is comparatively easy to estimate the thickness of plastically deformed layer.
4. The rate of pore area becomes smaller with the progress of cutting.
5. It is easy to measure the plastically deformed layer thickness of ferrous sintered steels in order of microhardness, internal pores area and microstructures.
