抄録
A Ni-4.5B-46.9Mo-12.5V (mass%) model alloy made from four kinds of boride powders (MoB, Mo2B, NiB and Ni2B) was prepared to study the effects of boron source on the microstructure and mechanical properties. The alloy made from Ni2B powder showed a very fine ideal two phase microstructure with homogeneous distribution of a tetragonal M3B2 (M: Mo, Ni and V)type complex boride in the Ni base binder and hence exhibited excellent transverse rupture strength (TRS) higher than 3 GPa. The strength of the alloy made from the other boride powder exhibited 2.2-2.6 GPa. Carbon base impurities in the boride powders lead to the formation of carbides which caused deterioration of the mechanical property. The carbide formation changed the composition of the tetragonal boride phase and hence the hardness.
