Abstract: A disclosure is directed to a method for rapidly nitriding steel, the method including: placing the steel in a furnace having an atmosphere comprising partially dissociated ammonia gas; heating the steel to a highest temperature in a range of 400 to 600° C. while holding a nitriding potential below 15 atm?1/2 during heat-up from 400° C. up to the highest temperature; and holding the steel at the highest temperature while continuing to maintain the nitriding potential below 15 atm?1/2, where a total time taken for the heating and holding the steel in the range of 400 to 600° C. during the nitriding is 15 hours or less, and where a composition of the steel comprises at least one of the group consisting of Al, Cr, Mo, V, and Ti.

Abstract: A disclosure is directed to a method for rapidly nitriding steel, the method including: placing the steel in a furnace having an atmosphere comprising partially dissociated ammonia gas; heating the steel to a highest temperature in a range of 400 to 600° C. while holding a nitriding potential below 15 atm?1/2 during heat-up from 400° C. up to the highest temperature; and holding the steel at the highest temperature while continuing to maintain the nitriding potential below 15 atm?1/2, where a total time taken for the heating and holding the steel in the range of 400 to 600° C. during the nitriding is 15 hours or less, and where a composition of the steel comprises at least one of the group consisting of Al, Cr, Mo, V, and Ti.

Abstract: A method of forming an oxide layer on a powder metal part includes subjecting the powder metal part to a steam oxidation process. An oxide layer is formed on the powder metal part. The oxide layer has a thickness greater than 7 microns.

Abstract: An article and method for forming an article having a hard-finished surface including a predetermined density of carbides to improve pitting and wear resistance and to significantly increase the overall life of the article. This method comprises selecting a carburizing grade material to form an article, carburizing the article to form a microstructure on at least one portion of the article having a predetermined density of carbides dispersed in the microstructure to a predetermined depth, quenching the article to form a hardened matrix dispersed with carbides and hard finishing the article to form the surface, the surface having at least approximately 20% by volume fraction carbides dispersed in the hardened matrix.

Abstract: A method and apparatus for characterizing a quench for producing desired hardness characteristics on a steel part. The characterization preferably includes a series of heat transfer coefficients versus temperature for the quench determined from information representative of known quenches and distinguishing part characteristics such as geometry, size and composition. The quench characterization determined using the present method and apparatus can be utilized in hardness prediction software programs, and for determining a suitable quench for producing the desired hardness characteristics on the part.

Abstract: A process for improving fatigue resistance of a case hardened component having a case thickness "t", subjected to one or more of rolling, sliding, abrasion, bending and pitting includes determining the magnitude of fatigue strength at surface and at a plurality of pre-selected points along thickness "t" of a component. The applied fatigue stresses acting upon the component at the surface and at the plurality of pre-selected points along thickness "t" are also determined. Then, a compressive residual stress profile is tailored from the surface to thickness "t" of the component. The compressive residual stresses at the surface and at the plurality of the pre-selected points along thickness "t" respectively have a magnitude sufficient to attain a net resultant stress which is at least 25% lower than the fatigue strength at the surface and the corresponding plurality of pre-selected points.

Abstract: A crankshaft is manufactured by providing a plurality of initially completely discrete crankshaft segments electron-beam welded together. Tubular bearing journals (12,14) having an inclined surface (30) are positioned in a groove (35,40) of a counterweight web (16) and a groove (50) of a crankshaft end (18). The discrete segments (12,14,16,18) are positioned and maintained in position by the interaction of inclined surfaces (30) and grooves (35,40,50) for electron-beam welding.