abstract |
A high-strength machinable ceramic capable of high-precision fine machiningnhas a coefficient of thermal expansion close to that of silicon and preferably anuniform blackish color which facilitates image processing of machined parts. Thenceramic comprises a main constituent and a sintering aid. The main constituentncomprises 30 - 59.95 mass % of boron nitride, 40 - 69.95 mass % of zirconia,noptionally up to 20 mass % of silicon nitride and 0.05 - 2.5 mass % (calculated as annelement) of at least one coloring additive, which is selected from C, Si, elements ofnGroups IIIA - IVB in the fourth period, elements of Groups IVA - VB in the fifthnperiod, elements of Groups IVA - VIB in the sixth period of the long form periodicntable, and compounds of these elements. |