High modulus wear resistant gray cast iron for piston ring applications
AssigneeFederal-Mogul Corporation
InventorHaron Ogega Gekonde
Life of this patent
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Abstract
A piston ring formed of cast iron provides improved machinability and exceptional performance and minimum costs. The cast iron includes 2.2 to 2.9 wt. % carbon, 3.2 to 4.2 wt. % silicon, 0.75 to 1.25 wt. % copper, 1.0 to 1.5 wt. % manganese, 0.09 to 0.15 wt. % sulfur, not greater than 0.2 wt. % phosphorous, and an average carbon equivalent of 3.8. The cast iron preferably includes a matrix of martensite with MnS and carbides dispersed therein. The matrix is also preferably free of ferrite, austenite, and steadite. The cast iron is formed by casting, austenitizing, quenching, and tempering the alloy.
Claims16
A method of manufacturing a piston ring formed of cast iron, comprising the steps of:
- providing an alloy including, in weight percent (wt. %) of the alloy, 2.2 to 2.9 wt. % carbon, 3.2 to 4.2 wt. % silicon, 0.75 to 1.25 wt. % copper, 1.0 to 1.5 wt. % manganese, 0.09 to 0.15 wt. % sulfur, and not greater than 0.1 wt. % phosphorous;
- casting the alloy;
- austenitizing the alloy;
- quenching the austenitized alloy;
- and tempering the alloy to form cast iron, wherein the cast iron comprises manganese sulfide (MnS) and carbides.
A method of forming a cast iron, comprising the steps of:
- providing an alloy including, in weight percent (wt. %) of the alloy, 2.2 to 2.9 wt. % carbon, 3.2 to 4.2 wt. % silicon, 0.75 to 1.25 wt. % copper, 1.0 to 1.5 wt. % manganese, 0.09 to 0.15 wt. % sulfur, and not greater than 0.1 wt. % phosphorous;
- casting the alloy;
- austenitizing the alloy;
- quenching the austenitized alloy;
- and tempering the alloy to form cast iron, wherein the cast iron comprises manganese sulfide (MnS) and carbides.
Dependencies are inferred from the claim text.