CUTTING PERFORMANCE OF ACID ETCHED CERAMIC TOOLS.

Nine commercial ceramic tools were randomly selected and etched in HF acid for periods up to thirty minutes to alter surface characteristics of the ceramic tools to determine the effect of an impact resistance in interruped cutting. All treated and non-treated tools were randomly tested in machining of grooved ALSL-4340 steel test bars until complete failure. Each of the treated ceramic tools showed considerable improvement in the number of impacts to failure compared to the non-treated tools of the same grades. In all cases, therefore, shock resistance improvements were effected by the acid etching treatments.