A powder metallurgy mixture having of a composition (excepting incidental impurities) of 55-90% iron-based matrix powder 4 and 45-10% hard phase powder 2, wherein the hard phase has a composition (excepting incidental impurities), with at least some of each of the following elements (by weight): 1-3% C, 20-35% Cr, 2-22% Co, 2-15% Ni, 8-25% W, 0-5% total of V, Ti and Cu, with the balance and at least 30% being Fe. The iron based matrix powder may be a high chrome steel powder (16-20% Cr, 10-15% Ni, 0.1-5% Mo, 0-2% C balance Fe), a low alloy steel powder (containing not more than 19.6% of non-iron constituents, 0-2% C, 0-2% Mo, 0-5% Cu, 0-5% Cr, 0-5% Ni, 0-6% of one or more of Mn, P or S) or a tool steel powder (0-2% C, 3-7% Mo, 4-8% W, 2-6% Cr, 0.5-4% V, balance Fe and impurities). Material containing the low alloy steel powder or the tool steel powder may be infiltrated with copper 6 during sintering. MnS 8 may be added as a machinability aid and/or CaF2, MoS2, talc, graphite, BN or BaF2 added as a solid lubricant. The material may be used for valve seats and turbocharger bushings.
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