Polishing is the final step in production a surface that is flat,
scratch free, and mirror like in appearance. Such a surface is
necessary for subsequent accurate metallographic interpretation,
both qualitative and quantitative. The polishing technique used
should not introduce extraneous structure such as disturbed metal,
pitting, dragging out of inclusions, comet tails and staining.
Before final polishing is started, the surface condition should be
at least as good that obtained by grinding with a 400-grit (25
microns) abrasive.
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