Abstract:
Cryogenic cooling is a promising new technology in high production
machining which economically addressed the current process environmental
and health concern. High production and finish machining are inherently
associated with generation of intense heat and cutting temperature at the cutting
zone. Such high cutting temperature not only reduces tool life but also impairs
the surface integrity of the job. So the temperat~re at the cutting tool interface is
one of the important factors influencing the machining process while primarily
dependent on the cutting speed and the work piece material properties as well
as cutting tool properties. So, the benefits of cryogenic cooling are dependent
on the process parameters and the tool geometry.
Beneficial effects of proper cryogenic cooling on machining by uncoated
carbide inserts and grinding by conventional wheels in terms of technological
benefits and environment friendliness have already been established in number
of previous investigations. Substantial cooling and favorable interactions at the
chip-tool interface and work-tool interface as well as retention of tools-sharpness
were reportedly found to be the main reasons behind these technological
benefits of cryogenic machining. The present work deals with experimental
investigation in the role of cryogenic cooling by liquid nitrogen jet on cutting
temperature, chip formation mode, tool wear, surface finish and dimensional
deviation in turning of AISI 8740 steel at industrial speed-feed combination by
coated carbide insert which are widely used for high speed turning of plain
carbon and low alloy steels.
