Abstract:
Hard turning is a profItable alternative hl finish grinding in respect of dimensional
accuracy and surface finish to fulfill functional requirement. improved perfonnance and
prolonged service life llf the product. Hard turning is able to reduce processing time,
production cost, ,urfacc roughness and ~elUptime appreciably in comparlson to grinding.
But high heat generation at high production machining increase tool wear and deteriorates
the job quality. The conventional cutting fluids are not that effeetlve in such situation.
Minimum quantity lubrication (MQL) is a suitable alt~'l"natlvein thi. regard,
In thi, research work, the effects of MQL on cutting perfonnance of hardened
AISl4320 steel in respect of chip f<,nnalion, chip-tool interface lemperarure, tool "ear and
produel quality have been ~tudicd using coated carbide insert (SNMG-TN 4000). Three
types of culling fluids (soluble oil, vegetable oil and VO 68 cutting oil) have been used to
compare the relative performance of th'l'>e culling fluids with each olher as well as with
that of dry condition,
Compared to dry condition, MQL performed better mainly due to substantial
reduction in culling temperature that enabling favorable chip-tool int~'l"actlon.This also
facj]jtated the substantial reduction in tmll "ear. dimensional inaccumcy and surface
roughness. The result:>indicatcd that the u,e of minimum quantity lubrication (MQL) by
VG 68 cutting oil pcrformed better in comparison to other cutting fluids in respect of chips
formation mode. culling temperature, to"l wear, surface roughness and dimcnslonal
devialion,
