Machining of polymeric composite materials is an area still full of open qu
estions, pertaining to the assessment of machining and thermal aspects comp
ared to metal cutting. Due to the particular nature of composite materials,
precise analysis still lacks progress. In this investigation, face-turning
trials were performed on carbon/phenolic ablative composites using polycry
stalline diamond tools. Observations on specific cutting pressure and machi
ning temperature revealed the existence of a critical velocity of machining
. A range of machining temperature has been identified for effective machin
ing of the composite material, beyond which tool deterioration and thereby
the specific cutting pressure increases considerably. The study also enable
d the determination of the effective hardness of the tool material at which
steady machining can be performed. (C) 2000 Elsevier Science S.A. All righ
ts reserved.