Abstract: Disclosed is a flywheel assembly for recording and or reproducing devices which is produced by molding and sintering a mixture consisting principally of iron and graphite powders and, if necessary, a sulfur powder.

Abstract: A sintered alloy having improved wear resistance at high temperatures, comprising a soft, predominantly iron matrix having a Vickers hardness of 100-200 containing more than 5 but at most 20% Mo, together with 0.5-1.5% carbon and at least one additive selected from the group consisting of nickel, cobalt and chromium, with said additive constituting at most 25% by weight of said alloy, and most of said molybdenum being contained in Mo-Fe particles having a Vickers hardness of 600-1300 which are uniformly distributed within said matrix and have an average diameter of 20-70 microns.

Abstract: Iron-base sintered alloy for the valve seats of internal combustion engines is an iron-base alloy powder containing, by weight, 6 - 20% chromium less than 2.0% nickel, and carbon 0.2 - 1.5%, together with at least one additive selected from among 0.3 - 1.5% manganese, 0.2 - 1.5% sulfur, 0.5 - 8% molybdenum, and 0.5 - 2.5% silicon, and molded to a sintered density of 6.2 - 6.8 g/cm.sup.3.