HARD TURNING HAS THE POTENTIAL TO REPLACE GRINDING PROCESSES AND TO ACHIEVE SIGNIFICANT REDUCTIONS IN PRODUCTION TIME AND COST. TO GAIN ACCEPTANCE AS AN EQUIVALENT OF GRINDING, HARD TURNING MUST MEET HIGH QUALITY REQUIREMENTS OF FORM AND SIZE ACCURACY, SURFACE FINISH, AND SURFACE INTEGRITY OF THE WORKPIECE. ALSO, AS A RESULT OF MECHANICAL AND THERMAL INFLUENCES ON THE WORKPIECE SURFACE, RAPID SELF-COOLING CAN PRODUCE CHANGES OF THE MICROSTRUCTURE THAT APPEAR AS A WHITE LAYER UNDER A MICROSCOPE. THEREFORE, APART FROM TOOL WEAR, SURFACE INTEGRITY ASPECTS ARE CONSIDERED AND INFLUENCES ON THE FATIGUE STRENGTH OF COMPONENTS ARE DISCUSSED.