Use, in an application for
grinding, dispersion in a wet medium or surface treatment, of a
powder of sintered beads, said
powder having: - a
chemical composition such that, as percentages by
mass based on the
mass of the bead
powder: - (77 - C4)% ≤ W + Mo ≤ (97.5 - C3)%, with Mo ≤ 10%; - C1% ≤ C ≤ C2%; - 2.5% < additive ≤ 20.0%, the additive denoting Ti + Ta + Nb + V + Zr + Hf; - elements other than W, Mo, C, Ti, Ta, Nb, V, Zr, Hf, or "other elements": ≤ 3%; with: - C1 = 100*(C3 / C5), - C2 = 100*(C4 / C6), - C3 = k*C7, with k selected from 0.5, 0.6, 0.7, 0.8 and 0.9, - C4 = k'*C7, with k' selected from 1.2 and 1.1, - C5 = [m(W) + m(Mo) + m(Ti) + m(Ta) + m(Nb) + m(V) + m(Zr) + m(Hf) + C3], - C6 = [m(W) + m(Mo) + m(Ti) + m(Ta) + m(Nb) + m(V) + m(Zr) + m(Hf) + C4], - C7 = M(C)*[(m(W) / M(W)) + (m(Mo) / M(Mo)) + (m(Ti) / M(Ti)) + (m(Ta) / M(Ta)) + (m(Nb) / M(Nb)) + (m(V) / M(V)) + (m(Zr) / M(Zr)) + (m(Hf) / M(Hf))], m(W), m(Mo), m(Ti), m(Ta), m(Nb), m(V), m(Zr) and m(Hf) being the
mass, in grams, of the elements W, Mo, Ti, Ta, Nb, V, Zr and Hf, respectively, and M(W), M(Mo), M(Ti), M(Ta), M(Nb), M(V), M(Zr), M(Hf) and M(C) being the
molar mass, in g / mol, of the elements W, Mo, Ti, Ta, Nb, V, Zr, Hf and C, respectively; - a crystallographic composition such that more than 60% of the crystalline phases present in said bead powder are in the form of
metal carbide(s), as percentage by mass based on the mass of the crystalline phases, said crystalline phases including at least one
carbide of at least one element from among Ti, Ta, Nb, V, Zr and Hf.