# US 10,246,767 B2 · Sliding element, internal combustion engine and process for obtaining sliding element > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,246,767 B2 - Document ID: US10246767B2 - Status: Granted - Kind: B2 - Application number: 15/301,370 - Filed: 2015-04-01 - Published: 2017-05-04 - Granted: 2019-04-02 - Earliest claimed: 2014-04-02 - Assignees: Mahle Metal Leve S/A; Mahle International GmbH - Applicants: Mahle Metal Leve S/A; Mahle International GmbH - Inventors: Juliano Avelar Araujo; Robert R. Banfield - Web page: https://patentgrep.com/patent/US10246767B2 ## CPC - C23C 14/0605: {Carbon} - C23C 8/24: Nitriding - C23C 14/022: {by means of bombardment with energetic particles or radiation} - C23C 14/024: {Deposition of sublayers, e.g. to promote adhesion of the coating (C23C14/027 takes precedence)} - C23C 14/025: {Metallic sublayers} - C23C 14/16: on metallic substrates or on substrates of boron or silicon - C23C 14/325: {Electric arc evaporation} - C23C 16/50: using electric discharges {(generation and control of plasma in discharge tubes for surface treatment H01J37/32, H01J37/34)} - C23C: COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL (making metal-coated products by extrusion B21C23/22; covering with metal by connecting pre-existing layers to articles, see the relevant places, e.g. B21D39/00, B23K; metallising of glass C03C; metallising mortars, concrete, artificial stone, ceramics or natural stone C04B41/00; enamelling of, or applying a vitreous layer to, metals C23D; treating metal surfaces or coating of metals by electrolysis or electrophoresis C25D; single-crystal film growth C30B; by metallising textiles D06M11/83; decorating textiles by locally metallising D06Q1/04) ## Abstract A sliding element for internal combustion engines may include a ferrous base provided with a film applied upon a sliding surface. The film may have, sequentially, a metal connecting layer, a transitional layer, and a contact layer. The transitional layer may include a carbide containing a metal element. The contact layer may contain DLC (diamond-like carbon) doped with the metal element of the transitional layer, the DLC containing a maximum of 2% hydrogen by weight. An atomic ratio between metal and carbon in the contact layer in terms of a ratio Me/C is equal to or less than 0.1. ## Claims ### Claim 1 A sliding element for internal combustion engines, comprising a ferrous base provided with a film applied upon a sliding surface, the film having, sequentially, a metal connecting layer, a transitional layer, and a contact layer, wherein: the transitional layer includes a carbide containing a metal element; the contact layer contains DLC (diamond-like carbon) doped with the metal element of the transitional layer, the DLC containing a maximum of 2% hydrogen by weight; an atomic ratio between metal and carbon in the contact layer in terms of a ratio Me/C is equal to or less than 0.1; and the connecting layer includes one of chromium, nickel or cobalt having a face centred cubic (fcc) structure. ### Claim 2 (depends on 1) A sliding element according to claim 1, wherein the contact layer includes amorphous carbon (ta-C or a-C) doped with the metal element, the metal element being a maximum of 5% atomically. ### Claim 3 (depends on 1) A sliding element according to claim 1, wherein the metal element utilised in the transitional and contact layers is one of tungsten, chromium or niobium. ### Claim 4 (depends on 1) A sliding element according to claim 1, wherein the contact layer includes a layer of hydrogen-free DLC doped with the metal element, wherein the layer of DLC is nanostructured or amorphous. ### Claim 5 (depends on 1) A sliding element according to claim 1, wherein the carbon of the contact layer has structures of sp3 and sp2, in such manner that a ratio between integrated intense D and G bands in a Raman spectrum lies between 0.2 and 1.0. ### Claim 6 (depends on 1) A sliding element according to claim 1, wherein the transitional layer includes tungsten carbide, chromium carbide, or niobium carbide. ### Claim 7 (depends on 1) A sliding element according to claim 1, wherein the transitional layer has a thickness which varies between 0.05 and 0.50 microns. ### Claim 8 (depends on 1) A sliding element according to claim 1, wherein a thickness of the film varies from 5 to 25 microns. ### Claim 9 (depends on 1) A sliding element according to claim 1, wherein a hardness of the film varies between 2500 HV and 5000 HV. ### Claim 10 (depends on 1) A sliding element according to claim 1, the base material consists of stainless steel containing 10% to 17% of one of chromium, carbon steel or cast iron. ### Claim 11 (depends on 1) A sliding element according to claim 1, further comprising a polycrystalline columnar layer of chromium having an fcc structure. ### Claim 12 (depends on 1) A sliding element according to claim 1, wherein the connecting layer is obtained through vapour deposition by means of any metal source. ### Claim 13 (depends on 1) A sliding element according to claim 1, wherein the layers containing metal are deposited by one of a PACVD (plasma assisted chemical vapour deposition) process or a PVD (plasma vapour deposition) process. ### Claim 14 (depends on 1) A sliding element according to claim 1, wherein the connecting layer is obtained by a cathodic arc process. ### Claim 15 (depends on 1) A sliding element according to claim 1, wherein the base receives a nitriding treatment or a PVD coating prior to receiving the connecting layer. ### Claim 16 (depends on 1) A sliding element according to claim 1, wherein the sliding element is one of a piston ring, tappet, bearing or pin. ### Claim 17 An internal combustion engine comprising a sliding element having a ferrous base provided with a film applied upon a sliding surface, the film having, sequentially, a metal connecting layer, a transitional layer, and a contact layer, wherein: the transitional layer includes a carbide containing a metal element; the contact layer contains DLC (diamond-like carbon) doped with the metal element of the transitional layer, the DLC containing a maximum of 2% hydrogen by weight; an atomic ratio between metal and carbon in the contact layer in terms of the ratio Me/C is equal to or less than 0.1; and the connecting layer includes one of chromium, nickel or cobalt having a face centred cubic (fcc) structure. ### Claim 18 A process for obtaining a sliding element for internal combustion engines, comprising: ion bombarding a ferrous base (2) to clean a surface of the sliding element which will receive a film; depositing a metal connecting layer; increasing flow of reactive gas to a maximum value such as to form a transitional layer; and depositing a contact layer under constant process conditions; wherein the connecting layer includes one of chromium, nickel or cobalt having a face centred cubic (fcc) structure. ### Claim 19 (depends on 18) A process according to claim 18, wherein the metal connecting layer is of tungsten. ### Claim 20 (depends on 18) A process according to claim 18, further comprising using at least two diametrically opposed targets of metal or graphite during the increasing of flow of reactive gas and depositing of the contact layer.