Tool wear mechanism in up-cut end milling of AISI 1050 at different feed rates

Abstract

In this study, the tool wear mechanism of a TiN coated carbide insert in up-cut end milling of AISI 1050 at different feed rates, was investigated. The diameter of the end mill holder that was used was 35 mm. The edge roundness of the used cutting insert was approximately 4 μm. The feed rate was varied from 2.5 μm/tooth to 150 μm/tooth at the cutting speed of 100–150 m/min. The axial depth of the cut was set at 1.0 mm and the radial depth of the cut at 5.13 and 17.5 mm. In dry conditions, the flank wear width, at the same real cutting length, increased rapidly with the feed rate and reached its maximum at 10 μm/tooth. When the feed rate was set at smaller than 10μm/tooth, the smallest tool wear occurred at the lowest cutting speed. Subsequently, the wear width decreased drastically to one third of the maximum. At this feed rate range, the larger wear width occurred at the lower cutting speed. With further increase of the feed rate, the wear width increased with the feed rate. The feed rate, at which the wear width started to increase, was lower at higher cutting speeds. The deference of tool wear in the radial depth of the cut, at the same number of cuts, increased with a feed rate smaller than 10 μm/tooth. When the feed rate exceeded 10 μm/tooth, the difference decreased according to the feed rate.

Keywords

• end milling
• carbon steel
• coated carbide
• edge roundness
• feed rate
• tool wear
• cutting force