# US 10,371,085 B2 · Cylinder liner and method of forming the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,371,085 B2 - Document ID: US10371085B2 - Status: Granted - Kind: B2 - Application number: 15/481,501 - Filed: 2017-04-07 - Published: 2017-07-27 - Granted: 2019-08-06 - Earliest claimed: 2014-01-28 - Assignees: Zynp International Corp. - Applicants: ZYNP International Corp. - Inventors: Xiaocai Qin - Web page: https://patentgrep.com/patent/US10371085B2 ## CPC - F02F 1/004: {Cylinder liners (F02F1/08, F02F1/16 take precedence)} - C22C 37/04: containing spheroidal graphite - C22C 37/10: containing aluminium or silicon - F02F: CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES - C22C: ALLOYS (treatment of alloys C21D, C22F) ## Abstract A high strength cast iron material for application in heavy duty diesel engines with Pa peak cylinder pressure greater than 240 bar is disclosed, the material a ductile material austempered to get a ausferrite matrix structure with higher mechanical properties than conventional cast iron materials available by using a designed low cost alloying cast material with heat treatment. Furthermore, the cylinder liner may be formed using novel heat treatment and/or fine honing processes to improve the properties thereof. ## Claims ### Claim 1 A cylinder liner comprising: a first portion including a first graphite morphology in a first matrix including iron; and a second portion including a second graphite morphology in a second matrix including iron, the first graphite morphology different from the second graphite morphology, the second portion including austempered ductile iron. ### Claim 2 (depends on 1) The cylinder liner of claim 1, wherein the first matrix and the second matrix are substantially the same. ### Claim 3 (depends on 1) The cylinder liner of claim 1, wherein the first matrix and the second matrix are different. ### Claim 4 (depends on 1) The cylinder liner of claim 1, wherein the first portion includes an inner surface of the cylinder liner. ### Claim 5 (depends on 1) The cylinder liner of claim 1, wherein the second portion includes an outer surface of the cylinder liner. ### Claim 6 (depends on 1) The cylinder liner of claim 1, wherein the first portion includes compact graphite iron. ### Claim 7 (depends on 1) The cylinder liner of claim 1, wherein one of the first portion and the second portion includes between about 3.55 wt % and about 3.65 wt % carbon. ### Claim 8 (depends on 1) The cylinder liner of claim 1, wherein one of the first portion and the second portion includes between about 0.005 wt % and about 0.06 wt % magnesium. ### Claim 9 (depends on 1) The cylinder liner of claim 1, wherein one of the first portion and the second portion includes at least four members of a group consisting of: (a) between about 3.55 wt % and about 3.65 wt % C; (b) between about 2.30 wt % and about 2.40 wt % silicon; (c) between about 0.45 wt % and about 0.50 wt % manganese; (d) between about 0.020 wt % and about 0.030 wt % phosphorous; (e) between about 0.15 wt % and about 0.25 wt % sulfur; (f) between about 0.80 wt % and about 0.90 wt % copper; (g) between about 0.30 wt % and about 0.40 wt % nickel; (h) between about 0.10 wt % and about 0.20 wt % molybdenum; (i) between about 0.005 wt % and about 0.06 wt % magnesium; and (j) substantially free from chromium. ### Claim 10 (depends on 9) The cylinder liner of claim 9, wherein one of the first portion and the second portion includes each of (a), (b), (c), (d), (e), (f), (g), (h), (i), and (j). ### Claim 11 (depends on 1) The cylinder liner of claim 1, wherein an inner surface of the cylinder liner is honed. ### Claim 12 A cylinder liner comprising: an inner surface including compact graphite iron; and an outer surface including austempered ductile iron. ### Claim 13 (depends on 12) The cylinder liner of claim 12, wherein the inner surface includes a first matrix including iron and the outer surface includes a second matrix including iron. ### Claim 14 (depends on 12) The cylinder liner of claim 12, wherein the first matrix and the second matrix are substantially the same. ### Claim 15 (depends on 12) The cylinder liner of claim 12, wherein the first matrix and the second matrix are different. ### Claim 16 (depends on 12) The cylinder liner of claim 12, wherein the compact graphite iron includes graphite in the form of vermicular structures or flakes. ### Claim 17 (depends on 12) The cylinder liner of claim 12, wherein the austempered ductile iron includes graphite in the form of nodular or spheroidal shapes. ### Claim 18 (depends on 12) The cylinder liner of claim 12, wherein one of the first portion and the second portion includes between about 3.55 wt % and about 3.65 wt % carbon and between about 0.005 wt % and about 0.06 wt % magnesium. ### Claim 19 A cylinder liner comprising: an inner portion including a first graphite morphology in a first matrix including iron; and an outer portion including a second graphite morphology in a second matrix including iron, the outer portion having an ultimate tensile strength that is at least 200 MPa greater than an ultimate tensile strength of the inner portion, the second portion including austempered ductile iron.