Piston Ring Material For Internal Combustion Engine

Abstract

A piston ring material that when formed into a piston ring product, maintains excellent properties, and that at the production of piston ring rod, realizes excellent processability and shape stability. There is provided a piston ring material for internal combustion engine comprising, by mass, 0.5 to less than 0.7% C, 1.0% or less Si, 1.0% or less Mn, 12.0 to 16.0% Cr, 3.0% or less Mo and/or W (Mo+½W), 0.02 to 0.14% N and the balance Fe and unavoidable impurities, wherein the relationship of contained C, N and Cr satisfies the formulae: 25≦43.22C (%)+42.45N (%)−0.02Cr (%)≦40, and 0.15≦0.92C (%)+0.67N (%)−0.03Cr (%)≦0.30.

1 . A method of producing a rod for a piston ring for an internal combustion engine comprising
 subjecting a piston ring material to cold drawing and/or cold rolling to give a desired sectional shape of the piston ring,   heating the piston ring material having the desired sectional shape to 1000 to 1100° C., and subjecting the heated material to quenching and subsequent tempering so as to form the rod for the piston ring, the rod having an adjusted hardness, and the piston ring material consisting of, by mass, 0.5% or more and less than 0.7% of C, 1.2% or less of Si, 1.0% or less of Mn, 12.0-16.0% of Cr, Mo and/or W in an amount that satisfies the formula (Mo+½W)≦3.0%, 0.04-0.13% of N, 0.1% or less of P, and 0.1% or less of S, with the balance Fe and unavoidable impurities, wherein the relationship of the contained C, N and Cr in the piston ring material satisfies the formulas of 29≦43.22C (%)+42.45N (%)−0.02Cr (%)≦40 and 0.15≦0.92C (%)+0.67N (%)−0.03Cr (%)≦0.30.   
     
     
         2 . The method according to  claim 1 , wherein C is contained in an amount of 0.60-0.68% by mass in the piston ring material. 
     
     
         3 . The method according to  claim 1 , wherein Cr is contained in an amount of 14.0-16.0% by mass in the piston ring material. 
     
     
         4 . The method according to  claim 1 , wherein the relationship of the contained C, Cr and N by mass % satisfies the formulas of 29≦43.22C (%)+42.45N (%) -0.02Cr (%)≦35 in the piston ring material. 
     
     
         5 . The method according to  claim 1 , wherein the relationship of the contained C, Cr and N by mass % in the piston ring material satisfies the formulas of 0.18≦0.92C (%)+0.67N (%)−0.03Cr (%)≦0.30. 
     
     
         6 . The method according to  claim 1 , wherein Mo and/or W are containing in an amount that satisfies the formula (Mo+½W) is >1.5% to 3.0% by mass in the piston ring material. 
     
     
         7 . The method according to  claim 1 , wherein Mo and/or W are contained in an amount that satisfies the formula (Mo+½W) is 1.6-2.5% by mass in the piston ring material. 
     
     
         8 . The method according to  claim 1 , wherein Mo is selected from Mo and/or W in the piston ring material. 
     
     
         9 . The method according to  claim 1 , wherein Si is contained in an amount of 0.1-1.0% by mass in the piston ring material. 
     
     
         10 . The method according to  claim 6 , wherein Mo is selected from Mo and/or W in the piston ring material. 
     
     
         11 . The method according to  claim 7 , wherein Mo is selected from Mo and/or W in the piston ring material. 
     
     
         12 . A method for producing a rod for a piston ring for an internal combustion engine comprising
 subjecting a piston ring material to cold drawing and/or cold rolling to give a desired sectional shape of a piston ring,   heating the piston ring material having the desired sectional shape to 1000 to 1000° C. and subjecting the heated material to quenching and subsequent tempering so as to form the rod for the piston ring, the rod having an adjusted hardness, and   the piston ring material consisting of, by mass, 0.60-0.68% of C, 0.1-1.0% of Si, 1.0% or less of Mn, 14.0-16.0% of Cr, 1.6-2.5% of Mo, and 0.04-0.13% of N, 0.1% or less of P, and 0.1% or less of S, with the balance Fe and unavoidable impurities, wherein the relationship of the contained C, Cr and N in the piston ring material satisfies the formulas of 29≦43.22C (%)+42.45N (%)−0.02Cr (%)≦35 and 0.18≦0.92C (%)+0.67N (%)−0.03Cr (%)≦0.30.   
     
     
         13 . A method for producing a rod for a piston ring for an internal combustion engine comprising
 subjecting a piston ring material to cold drawing and/or cold rolling to give a desired sectional shape of a piston ring,   heating the piston ring material having the desired sectional shape to 1000 to 1100° C. and subjecting the heated material to quenching and subsequent tempering so as to form the rod for the piston ring, the rod having an adjusted hardness, and   the piston ring material consisting of, by mass, 0.5% or more and less than 0.7% of C, 1.2% or less of Si, 1.0% or less of Mn, 12.0-16.0% of Cr, Mo and/or W in an amount that satisfies the formula (Mo+½W)≦3.0%, 0.04-0.13% of N, 0.1% or less of P, and 0.1% or less of S, with the balance Fe and unavoidable impurities, wherein the relationship of the contained C, N and Cr in the piston ring material satisfies the formula of 29≦43.22C (%)+42.45N (%)−0.02Cr (%)≦40 and 0.15≦0.92C (%)+0.67N (%)−0.03Cr (%)≦0.30, and wherein the material has a reduction of area of 45% or more according to a tensile test.   
     
     
         14 . The method according to  claim 1 , wherein Mo and/or W are contained in an amount that satisfies the formula (Mo+½W) is 2.5% or less by mass in the piston ring material. 
     
     
         15 . The method according to  claim 14 , wherein Mo and/or W are contained in an amount that satisfies the formula (Mo+½W) is 1.7% or less by mass in the piston ring material. 
     
     
         16 . The method according to  claim 12 , wherein Mo is contained in an amount of 1.7% or less by mass in the piston ring material. 
     
     
         17 . The method according to  claim 1 , wherein the hardness of the rod for the piston ring is adjusted to 35 HRC or more by tempering. 
     
     
         18 . The method according to  claim 12 , wherein the hardness of the rod for the piston ring is adjusted to 35 HRC or more by tempering. 
     
     
         19 . The method according to  claim 13 , wherein the hardness of the rod for the piston ring is adjusted to 35 HRC or more by tempering. 
     
     
         20 . The method according to  claim 13 , wherein Mo and/or W are contained in an amount that satisfies the formula (Mo+½W) is 2.5% or less by mass in the piston ring material.