Abstract: A method is disclosed for making gray iron having both increased wear resistance and impact toughness, comprising: (a) solidifying a hypoeutectic gray iron melt (i) to which has been added a eutectic carbide forming agent in an amount of 0.3-0.8% by weight, selected from the group consisting of Ti, V and Cr, and, advantageously, a high carbon austenite/ferrite forming agent in an amount of 0.5-3.0%, by weight, selected from the group consisting of nickel and copper, and at a solidification rate to form an austenite matrix with a mixture of flake graphite and eutectic carbide particles suspended in said matrix; and (b) heat treating the solid by (i) heating to a temperature and for a period of time to fully austenitize the solid, (ii) quenching the solid to a temperature level and for a period of time to decompose austenite to form a high carbon austenite and ferrite matrix, and (iii) air cooling the solid to room temperature. The hypoeutectic gray iron contains less than 4.

Abstract: An apex seal consisting of 3.0 to 4.0 wt % of C, 1.5 to 2.5 wt % of Si, 0.3 to 1.0 wt % Mn, 0.05 to 0.3 wt % of P, less than 0.1 wt % of S, 0.005 to 0.025 wt % of Mg or Ce, 0.5 to 2.0 wt % of Cu and/or 0.5 to 3.0 wt % of Ni, 0.4 to 1.0 wt % of Cr, 1.0 to 2.0 wt % of Mo and/or 0.1 to 0.5 wt % of V with the balance of Fe, being formed in the sliding surface portion with a sorbite matrix structure in which carbides are dispersed in a matrix of sorbite and in the matrix portion of the material other than the sliding surface portion with a sorbite structure. The apex seal has an excellent bending strength and wear resistance.

Abstract: Austenitic cast iron has excellent corrosion resisting properties and has been preferentially used in machines or machine parts intended for handling corrosive fluids such as seawater. Cases, however, have been reported of machines or machine parts made of austenitic cast iron failing after they had been put to prolonged service at relatively low temperatures. The present inventors have located stress corrosion cracking at the cause of this failure.In accordance with the present invention, methods of using salt water resisting machines or machine parts made of austenitic cast iron that has graphite in the form of spheroids or nodules and which comprises by weight %: C.ltoreq.3.0, Si=1.0-3.0, Mn.ltoreq.1.5, P.ltoreq.0.08, Ni>24-28%, Cr.ltoreq.5.5 and the balance being Fe to minimize stress corrosion are provided.

Abstract: The work-performing member for a farm machine has a cutting edge made of a high-carbon steel containing graphite in structurally free state in an amount of 0.5 to 1.32 percent of the total mass of the material.

Abstract: This invention relates to a heavy wall monolithic iron pipe comprising nodular graphite in the outer portion of its wall and flake or quasi-flake graphite in the inner portion of its wall and a method for making said pipe. The central portion of the wall of the pipe may be a combination of nodular graphite and flake or quasi-flake graphite.

Abstract: A method is disclosed which comprises: (a) forming a ferrous alloy melt consisting essentially of by weight, 3-4% carbon, 2.0-3.0% silicon, 0.1-0.9% manganese, up to 0.02% phosphorus, up to 0.002% sulphur, up to 1% contaminants or impurities, 0-0.4% molybdenum, 0-3.0% nickel or copper, and the reminder essentially iron, the melt being subjected to a graphite modifying agent in an amount and for a period of time effective to form either ductile or semiductile iron upon solidification; (b) heat treating the solidification of said melt by austempering to form a matrix consisting substantially of high carbon austenite and ferrite and a cell boundary having unreacted low carbon austenite; (c) heating said austempered iron to a pearlite forming temperature (1200.degree.-1300.degree. F.) and holding (2-5 minutes) at said temperature to permit the unreacted low carbon austenite to form pearlite; and (d) cooling said heat treated iron to room temperature.

Abstract: This invention concerns an improvement in cast iron material and chilled iron material. The cast iron material has a C.E. value of not more than 4.3 in which cerium is added in the form of a mischmetal upon casting to a cerium content of from 0.005 to 0.035 wt %. The chilled cast iron article has a chilled layer formed by remelting at least a portion of the surface of the cast iron of a predetermined shape composed of the above-mentioned cast iron by a high density energy source such as tungsten inert gas (TIG) arc, laser or electron beam.

Abstract: A method is disclosed for forming a surface hardenable cast iron article by development of metastable retained austenite in the cell boundary of a ductile or semiductile cast iron. The method comprises (a) controlling the solidification of a cast iron melt to extend the eutectic arrest time to 4-12 minutes, the melt having by weight percent a carbon equivalent (carbon plus one-third silicon) equal to 4.3-5.0, manganese 0.55-1.2, nickel 0.5-3.0, and the remainder essentially iron, the melt having been treated to form cell boundaries in the solidified iron with a high proportion of the manganese being segregated in the cell boundaries; (b) subjecting the solidified cast iron to an austempering heat treatment to permit the segregated manganese in the cell boundaries to form metastable retained austenite; and (c) terminating the heat treatment prior to the conversion of the metastable austenite to a stable microstructure.

Abstract: A method is disclosed for improving the immunity to temperature changes of cast iron containing lamellar graphite. The structure of the cast iron melt is suitably adjusted by means of carbide forming agents, to wit chromium and/or molybdenum and an annealing treatment in such a manner that the gray cast iron withstands increased thermal shock and dynamic stresses.

Abstract: In order to prevent the formation of fissures or tears in the walls of cylinders of an internal combustion engine, hardening tracks (4) generated by a carbon dioxide laser, are placed parallel to each other at an angle of inclination (.alpha.) with respect to the axis (3) of the wall of the cylinder or cylinder liner, and spaced from each other by a distance (X) which is greater than twice the distance (k) between the maxima (9, 10) of tension resulting in the operation of the ICE from the edges of the hardening track, thereby satisfying the condition: X is greater than 2.times.k.