Feasibility Study on the Minimum Quantity Lubrication in High-Speed Helical Milling of Ti-6Al-4V

Abstract

The objective of the present work was to study the effect of theapplication of minimum quantity lubrication (MQL) in high-speed helicalmilling of Ti-6Al-4V compared with dry and flood coolant (wet)condition. The single factor experiment to study the relationshipbetween cutting force, hole surface roughness and cutting parametersunder various coolant-lubricant conditions were implemented. Tool lifeunder various cooling conditions and fixed moderate cutting parametershave also been studied. Uniform flank wear, micro-chipping, thermalcracking and flaking were the dominant tool failure modes under allcoolant-lubricant conditions. It was found that dry condition producedthe poorest result in terms of cutting force, tool life and hole surfaceroughness as general expected. MQL presented comparable performance withflood condition in terms of cutting force and hole surface roughness,and even a better tool life performance than flood condition. Thistestified the flood condition can be replaced by the MQL condition, thusalleviating pollution and saving cost during helical milling ofTi-6Al-4V process.