Patent ID: 6043176
Filing Date: 2000-03-28
Classification: C04B,Y10T

Abstract:
A method of manufacturing a sintered ceramic material for high speed machining of heat resistant alloys said ceramic comprising SiAlON and 0.2-20 v/o intergranular phase whereby at least 80 v/o of said SiAlON phase is beta SiAlON (Si.sub.6 --.sub.z Al.sub.z O.sub.z N.sub.8-z), having a z-value greater than 1.0, but less than 1.5, said sintered ceramic material having a Vickers Hardness HV1 of more than 1530, said method comprising mixing precursor powders, pressing the precursor powders to form blanks and sintering the blanks using gas pressure sintering whereby the final part of the sintering takes place at 1700.degree. C.-1800.degree. C. and 10-15 bar nitrogen for 1-3 hours.