Reaction sintered cermet

Claim 1

A reaction sintered cermet body consisting of a fine-grained, homogeneous, intimate interdispersion of: (a) 40-95 mole percent of first phase or phases having a maximum grain size substantially not greater than 10 μm and being boride, nitride, silicide, sulfide or combination thereof of one or more of the elements of Groups 2a, 3a exclusive of B, 4a, 2b, 3b including lanthanide and actinide series elements, 4b, 5b, 6b, 7b and 8; (b) 5-60 mole percent of second phase or phases being metal, alloy, intermetallic compound or combination thereof of one or more of the elements of Groups 3a exclusive of B, 4a, 2b, 4b, 5b, 6b, 7b, iron, cobalt and nickel; and (c) optionally diluent selected from nonreacted portion of reactants forming the first and second phases and preformed material that is the same as the first and/or second phases; which body contains 0 to 4 weight percent oxygen and is prepared by the process comprising: (d) admixing particulate exothermic reactants of maximum particle size substantially not greater than 150 μm and being elements, compounds, intermetallic compounds, alloys or combination thereof in stoichiometric proportions to substantially form the first and second phases, and (e) shaping and heating the admixture to form the reaction sintered body, and heating being done in nonreactive atmosphere and at temperature at which the reaction and sintering occurs between the reactants to substantially form the first and second phases.