Abstract:
High production machining, grinding and drilling inherently generates large
amount of heat leads to high cutting zone temperature for its higher cutting
velocity, feed and depth of cut Such high cutting temperature if not reduced
impairs surface integrity of the product and reduce dimensional accuracy as well
as tool life. Application of cutting fluids changes the performance of machining
operations because of their lubrication, cooting, and chip flushing functions.
However, the conventional cutting fluids are not that effective in such high
production drilling. Low boiling temperature cause vaporization of cutting fluid
and prevent it 10enler inlo cutting interface making a barrier to flow, In addition,
flowing chips through drill flute prevent the fluid to enter into the cutting zone.
Further, they (liso deteriorate the working environment and lead to general
environmental pollution.
High-pressure coolant presents itself as a viable alternative for drilling with
respect to heat dissipation, roundness deviation and taper of the hole, chip
formation mode and tool wear. This study compares the mechanical
performance of high-pressure coolant to completely dry lubrication for the
drilling of AISI-4340 steel and AISI-1040 steel based on experimental
measurement of roundness deviation and taper of the hole, chip formation
mode and tool wear, Results indicated that the use of high-pressure coolant
leads to lower roundness deviation and taper of the hole, favorable chip-tool
interaction and reduced tool wear.
