Effect of High Speed Dry End Milling on Surface Roughness and Cutting Forces of Ti-6Al-4V ELI

Abstract

The surface quality generated when high speed dry end milling (HSDEM) Ti-6Al-4V-ELI titanium alloy with coated and uncoated carbide tools were investigated. Evaluation was conducted using TiAlN+TiN coated and uncoated cemented carbide tools under different high cutting speeds and feed rates conditions. Surface roughness and cutting forces were measured when using new tools. The milled surface quality and corresponding alteration were characterized through electron microscopy. Within the investigated conditions high quality surface finish was obtained on the machined surface. Increasing cutting speed from 200 to 300 m/min during the process improved the surface finished particularly under lower feed rates. In term of generated surface quality, uncoated H25 grade carbide tools out performed coated F40M grade specifically at the higher cutting conditions. The main damages observed after HSDEM on the surface for all machining conditions contain redeposited materials, feed marks, and tool edge marks. Under both tested feed rates the resultant cutting force decreased by increasing the cutting speeds and uncoated carbide tools provide the lower cutting forces compared to coated types.

Cutting performance and surface quality of Ti-6Al-4V by longitudinal ultrasonic vibration-assisted high-speed dry milling with coated carbide tools

“…When the f z value was small, the milling forces in HSDM were lower than in the CM process. The TiAlN/TiN-coated tool did not signi cantly improve the surface roughness compared to the uncoated tool due to the detrimental effect of the large v c values [23]. The results indicate that even if a coated tool is selected, it is di cult to change the machined surface quality if the cutting parameters exceed the limit values of the coated tool.…”

Energy field-assisted high-speed dry milling green machining technology for difficult-to-machine metal materials

“…Even when using coated tools, the cutting parameters of HSDM should be reasonably selected. Safari et al [109] tested the surface roughness and microhardness of a workpiece surface under different cutting conditions with a PVD-coated tool (TiAlN/TiN) when v c ranged from 100 to 300 m/min and f z from 0.03 to 0.06 mm/z. As v c increased from 100 to 300 m/min, the surface roughness decreased by 55%.…”

“…The surface roughness decreased by 40% at a v c value of 100 m/min as f z increased from 0.03 to 0.06 mm/z. Tool wear and work-hardening problems were also observed when v c and f z increased simultaneously [109]. Furthermore, the researchers used the same PVD tool for the HSDM processing of TC4-ELI.…”