HARD METAL SUBSTRATE BODY AND METHOD FOR PRODUCING THE SAME

摘要

The invention relates to a hard metal substrate body consisting of a WC hard material phase and between 3 and 25 mass % of a binding phase containing at least one binding metal Fe, Co and/or Ni, and up to 15 mass % (in relation to the binding phase) of dissolved dopants from the group containing AI, Cr, Mo, Ti, Zr, Hf, V, Nb, Ta. The invention also relates to a method for producing one such hard metal substrate body, using powder metallurgy followed by sintering. According to the invention, the percentage of all of the dopants in the hard metal is limited to a maximum of 4 mass %, the proportion of cubic phase in the hard metal is less than 4 vol. %, and the binding metal content in an edge region of the hard metal substrate body falls from up to 1 mu m, preferably up to 0.5 mu m, to less than half the binding agent content inside the substrate body. In order to produce said hard metal substrate body, once the eutectic has been reached and at the latest once the sintering temperature has been reached in the heating phase, the vacuum or inert gas atmosphere is replaced by a N2 atmosphere and maintained at least until the sintering temperature is reached.