Reduction in Airborne Silicon Carbide Whiskers by Process Improvements

Abstract

Silicon carbide whisker toxicity references are listed to support the acceptable exposure limit for those whiskers. Difficulties in phase contrast microscopy analysis of samples collected during silicon carbide whisker-reinforced ceramic machining were overcome by using scanning electron microscopy. Fiber monitoring results are presented for machining of whisker-reinforced metals and ceramics. Exposures during green and presintered ceramic machining were reduced to acceptable levels by using local exhaust ventilation. Hood air flow velocities and volumes are listed. During fired ceramic grinding, exposures were reduced by removing grinding debris from the recirculated coolant.