The production and properties of ceramic cutting tools containing varying amounts of alumina, chromia, magnesia, zirconia and TiC with FeCr, Ti, Fe, Cr binders were investigated. Alumina, magnesia, FeCr powders were obtained from Seydisehir, Antalya, Konya (TR) and TiC from Sandvik (S); Ti and Cr from S.P.M.S.-Poudmel (F); and chromia from Merck (D). Some specimens were cold-compacted and vacuum-induction sintered and some were hot-pressed: Hot-pressing yielded a 10-30% increase in density and hardness values, and up to a 70% increase in thermal shock resistance. Induction heating was used throughout this work. The cutting tools thus produced were tested for density, porosity, hardness, volume shrinkage, thermal shock resistance and abrasion resistance, and were found to be quite satisfactory. The presence of Cr (30-70%), TiC (40%), Cr2O3 (15%) were observed to improve the density and hardness values. The FeCr matrix, when used in increasing proportions of 0-70%, had an undesirable influence on hardness. Thermal shock resistance was tested at 800 degrees C and was found to rise with FeCr or TiC and to decline with Cr2O3 additions. (C) 1997 Elsevier Science Ltd.
