Abstract: The present disclosure relates to heat-resistant, corrosion-resistant alloys to be used as materials for the exhaust valve of an internal combustion engine which contain specified amounts of C, Cr, Co, Fe, Ti, Al, Nb, and Ta.

Abstract: Ceramics adapted to be enveloped in a casting having a cumulative particle size distribution such that the percentage of particles with sizes of less than 44.mu. lies within the range of 14.5-50% and the balance consists of particles the maximum size of which ranges from 500-2,000.mu., in order to produce vibration-resistant ceramic parts which may be enveloped in a casting.

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: An upset-forged poppet valve wherein at least the head portion and a part of the neck is made of a high temperature super alloy while the remaining portion is made of a conventional valve steel, said two materials being connected by friction welding before said valve is forged. The method comprises two steps of first friction-welding two rods of said two materials and then forming the connected single rod into the poppet valve by upset-forging.

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.

Abstract: Apparatus for manufacturing spherical hollow particles which provides a large number of individual linear water jets arranged in a ring and converging at a single point, so that a molten metal may be passed through this ring of water jets and converging point.

Abstract: The present invention relates to an anti-wear ferrous sintered alloy composed of carbon, molybdenum, phosphorus, boron, and, if desired, copper, and the balance iron.

Abstract: A method for manufacturing spherical hollow particles by providing a large number of individual linear water jets arranged in a ring and converging at a single point, and passing a molten metal through this ring of water jets and converging point.