A productive and cost-effective CBN hard milling-based fabrication method of hardened sliding guideways made of refined cast iron

摘要

Sliding guideways have received renewed interest in recent years as machine tool linear motion guides, due to a demand for machine tools to have good dynamic performance, which is of vital importance when machining difficult-to-cut materials. While the traditional fabrication approach of the sliding surface is grinding, this paper investigated the possibility of an alternative cubic boron nitride (CBN) milling-based manufacturing approach while utilizing Al and Mg additives in the cast iron material for better machinability and productivity. Machining results have shown a dramatic improvement in machinability especially in terms of tool wear at certain cutting conditions with the refined hardened cast iron and a CBN tool. It was found by the post experimental analysis that oxide films of the Al and Mg additives were generated at the cutting edge of the CBN tool to protect the tool from wear. Because of suppression of tool wear, a very constant surface roughness can also be achieved. A case study has also demonstrated the effectiveness of the CBN milling-based manufacturing approach with the refined cast iron and the found high-speed cutting conditions.