EP0668375B1 - Process for forming composite galvanic coatings of hard chromium with a disperse phase, and wear-resistant coating formed thereby - Google Patents
Process for forming composite galvanic coatings of hard chromium with a disperse phase, and wear-resistant coating formed thereby Download PDFInfo
- Publication number
- EP0668375B1 EP0668375B1 EP95102258A EP95102258A EP0668375B1 EP 0668375 B1 EP0668375 B1 EP 0668375B1 EP 95102258 A EP95102258 A EP 95102258A EP 95102258 A EP95102258 A EP 95102258A EP 0668375 B1 EP0668375 B1 EP 0668375B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- microcracks
- layer
- particles
- matrix
- chromium
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 239000011651 chromium Substances 0.000 title claims description 49
- 229910052804 chromium Inorganic materials 0.000 title claims description 41
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 title claims description 40
- 238000000576 coating method Methods 0.000 title claims description 40
- 239000011248 coating agent Substances 0.000 title claims description 31
- 238000000034 method Methods 0.000 title claims description 21
- 239000002131 composite material Substances 0.000 title claims description 5
- 239000002245 particle Substances 0.000 claims description 41
- 239000011159 matrix material Substances 0.000 claims description 34
- 239000000758 substrate Substances 0.000 claims description 19
- 238000000151 deposition Methods 0.000 claims description 16
- 229910052755 nonmetal Inorganic materials 0.000 claims description 15
- PNEYBMLMFCGWSK-UHFFFAOYSA-N Alumina Chemical compound [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 10
- 239000000463 material Substances 0.000 claims description 9
- 238000007747 plating Methods 0.000 claims description 8
- 239000000725 suspension Substances 0.000 claims description 7
- 230000008021 deposition Effects 0.000 claims description 5
- 229910052739 hydrogen Inorganic materials 0.000 claims description 5
- 239000001257 hydrogen Substances 0.000 claims description 5
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 4
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 claims description 4
- 229910010271 silicon carbide Inorganic materials 0.000 claims description 4
- KRVSOGSZCMJSLX-UHFFFAOYSA-L chromic acid Substances O[Cr](O)(=O)=O KRVSOGSZCMJSLX-UHFFFAOYSA-L 0.000 claims description 3
- AWJWCTOOIBYHON-UHFFFAOYSA-N furo[3,4-b]pyrazine-5,7-dione Chemical compound C1=CN=C2C(=O)OC(=O)C2=N1 AWJWCTOOIBYHON-UHFFFAOYSA-N 0.000 claims description 3
- 229910052580 B4C Inorganic materials 0.000 claims description 2
- 229910052582 BN Inorganic materials 0.000 claims description 2
- PZNSFCLAULLKQX-UHFFFAOYSA-N Boron nitride Chemical compound N#B PZNSFCLAULLKQX-UHFFFAOYSA-N 0.000 claims description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 2
- 229910052581 Si3N4 Inorganic materials 0.000 claims description 2
- INAHAJYZKVIDIZ-UHFFFAOYSA-N boron carbide Chemical compound B12B3B4C32B41 INAHAJYZKVIDIZ-UHFFFAOYSA-N 0.000 claims description 2
- UFGZSIPAQKLCGR-UHFFFAOYSA-N chromium carbide Chemical compound [Cr]#C[Cr]C#[Cr] UFGZSIPAQKLCGR-UHFFFAOYSA-N 0.000 claims description 2
- JOPOVCBBYLSVDA-UHFFFAOYSA-N chromium(6+) Chemical compound [Cr+6] JOPOVCBBYLSVDA-UHFFFAOYSA-N 0.000 claims description 2
- 229910003460 diamond Inorganic materials 0.000 claims description 2
- 239000010432 diamond Substances 0.000 claims description 2
- 238000009826 distribution Methods 0.000 claims description 2
- 229910002804 graphite Inorganic materials 0.000 claims description 2
- 239000010439 graphite Substances 0.000 claims description 2
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 claims description 2
- 229910003470 tongbaite Inorganic materials 0.000 claims description 2
- UONOETXJSWQNOL-UHFFFAOYSA-N tungsten carbide Chemical compound [W+]#[C-] UONOETXJSWQNOL-UHFFFAOYSA-N 0.000 claims description 2
- 238000005260 corrosion Methods 0.000 description 4
- 230000007797 corrosion Effects 0.000 description 4
- 239000002270 dispersing agent Substances 0.000 description 4
- 229910001018 Cast iron Inorganic materials 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 3
- 229910052710 silicon Inorganic materials 0.000 description 3
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- WGLPBDUCMAPZCE-UHFFFAOYSA-N Trioxochromium Chemical compound O=[Cr](=O)=O WGLPBDUCMAPZCE-UHFFFAOYSA-N 0.000 description 2
- 229910052796 boron Inorganic materials 0.000 description 2
- 238000002149 energy-dispersive X-ray emission spectroscopy Methods 0.000 description 2
- 150000001247 metal acetylides Chemical class 0.000 description 2
- 150000004767 nitrides Chemical class 0.000 description 2
- 239000010703 silicon Substances 0.000 description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 238000005299 abrasion Methods 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 229910052593 corundum Inorganic materials 0.000 description 1
- 238000005315 distribution function Methods 0.000 description 1
- 238000004070 electrodeposition Methods 0.000 description 1
- 230000002708 enhancing effect Effects 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 238000007749 high velocity oxygen fuel spraying Methods 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 239000000314 lubricant Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000013011 mating Effects 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000001000 micrograph Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 230000001902 propagating effect Effects 0.000 description 1
- 230000003134 recirculating effect Effects 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 239000001117 sulphuric acid Substances 0.000 description 1
- 235000011149 sulphuric acid Nutrition 0.000 description 1
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 1
- 229910052721 tungsten Inorganic materials 0.000 description 1
- 239000010937 tungsten Substances 0.000 description 1
- 229910001845 yogo sapphire Inorganic materials 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D15/00—Electrolytic or electrophoretic production of coatings containing embedded materials, e.g. particles, whiskers, wires
- C25D15/02—Combined electrolytic and electrophoretic processes with charged materials
Definitions
- the present invention relates to a process for forming, on a substrate, a composite hard chromium coating comprising a disperse phase consisting of nonmetal particles; and to a wear-resistant coating formed using such a process and particularly suitable for mechanical components subjected to high-temperature chafing, such as internal combustion engine piston rings and components.
- US Patent n. 4,846,940 relates to galvanic hard chromium coatings characterized by a Cr matrix with a large number of micro- and macrocracks combined with a disperse phase, in the matrix, consisting of hard particles embedded in the micro- and macrocracks of the matrix.
- Such coatings are formed by means of a galvanic electrodeposition process characterized by comprising a current inversion step, i.e. by alternately switching the substrate from cathode to anode potential and vice versa.
- Such coatings present a small amount of incorporated hydrogen, a large number of even relatively large cracks, and a large number of particle inclusions in the cracks, which make them highly susceptible to corrosion. Moreover, depositing the coating by inverting the polarity of the electrodes poses practical problems which complicate the fabrication process.
- a process for forming, on a substrate, a composite hard chromium coating comprising a disperse phase and particularly suitable for mechanical components subjected to high-temperature chafing comprising the step of galvanically depositing at least one layer of hard chromium in a chromium plating bath of the type forming microcracks and in which is dispersed in suspension a predetermined concentration of given sized particles of a nonmetal insoluble in the bath; characterized in that, in the course of said deposition step, the substrate is maintained permanently at cathode potential; and a pulsating cathode current, varying cyclically in time between a minimum and maximum value, is supplied to achieve a chromium layer comprising a matrix with microcracks of a given distribution, and a disperse phase consisting of said nonmetal particles, some of which are included in the microcracks, and some of which are directly embedded in the matrix, said chromium plat
- This provides for achieving a so-called "disperse chromium" coating comprising a Cr matrix containing dispersing agents, which is extremely hard (over 1,000 Vickers), includes dispersing agents in the form of nonmetal particles of hard materials such as oxides, carbides and nitrides of very low thermal conductivity and high thermal stability, and which, combined with a low hydrogen content, presents a high degree of thermal stability characterized by a reduced loss in hardness alongside an increase in temperature, and a small amount of incorporated hydrogen in the Cr matrix.
- variation of the cathode current may be achieved easily using known facilities, and fully automatically by means of appropriate programming, thus enabling troublefree, low-cost formation of the coating according to the present invention.
- the above deposition step is preferably preceded by the step of depositing on the substrate a continuous hard chromium base layer with substantially no microcracks or porosity, which covers the whole of the substrate, and which is formed, preferably to a thickness of roughly 50 ⁇ m, by galvanically depositing chromium in a chromium plating bath of the type forming no microcracks and containing no particles in suspension.
- a number of said "disperse" layers comprising a microcracked Cr matrix and including hard particles are then deposited successively on the continuous base layer.
- the substrate-coating interface thus presents a fairly thick layer (in relation to the total thickness of the coating, which is roughly 500 ⁇ m) with absolutely no cracks or dispersing agent particles (at least none detectable by standard metallographic techniques), and which prevents the microcracks in the upper layers of the coating from propagating towards the substrate, thus ensuring absolute protection of the substrate and greatly enhancing the corrosion resistance of both the substrate and the coating.
- the cathode current is supplied according to a cycle comprising the following steps:
- the cathode current is varied in a square wave pattern; and in said first and third steps, it is varied in steps.
- the "disperse chromium" layers are therefore formed with the microcracks of one layer offset, depthwise of the coating, in relation to those of the adjacent "disperse” layers, so that any depthwise propagation of the microcracks in one layer (due to mechanical stress in the layer) is prevented from being transmitted to those of the adjacent underlying layer, thus preventing the formation of macrocracks as in galvanic Cr coatings formed using known processes.
- This provides for obtaining a much more stable coating, and for further improving the corrosion resistance of the substrate, without, however, affecting the in-service lubricant collecting and distribution function of the microcracks.
- nonmetal dispersing agent particles substantially consisting of oxides (e.g. aluminium oxide - Al 2 O 3 ) and/or carbides (tungsten, chromium, silicon, boron) and/or nitrides (silicon, boron), i.e. extremely hard compounds, and both included inside the microcracks and embedded directly in the chromium matrix, provides for obtaining a coating which is extremely resistant to wear caused by abrasion or adhesion typical of high-temperature, mutually sliding metal surfaces.
- oxides e.g. aluminium oxide - Al 2 O 3
- carbides tungsten, chromium, silicon, boron
- nitrides silicon, boron
- the coating according to the present invention therefore comprises a layer comprising a microcracked hard chromium matrix and a disperse phase, in the matrix, consisting of a number of particles of a nonmetal material; a first number of said particles being included in the microcracks of the matrix, and a second number of said particles being embedded directly in parts of the matrix with no microcracks; characterized in that it comprises a first hard chromium layer with substantially no microcracks or porosity and without said particles; and, deposited on the first layer, a number of said layers comprising a microcracked matrix and a disperse phase consisting of said particles; the superimposed layers, deposited on the first layer, presenting the microcracks offset depthwise in relation to those of the adjacent layers.
- the first layer presents a thickness of at least 50 ⁇ m; the width of the microcracks, measured parallel to the layer, is at least 1 ⁇ m; the density of the microcracks ranges from 100 to 300 per centimeter; and the size of the nonmetal particles embedded in the matrix ranges from 0.1 to 20 ⁇ m.
- cylinder liners such as the piston rings of four- and two-stroke engines or piston pumps
- the cylinder liners are normally made of lamellar, nodular or vermicular cast iron, either natural or hardened (e.g. laser quenched) or nitrided (e.g. using the TENIFER (registered trade mark) process or similar), or present surfaces with hot spray coatings such as FK1008 formed using the HVOF process (both registered trade marks).
- Number 1 in Figure 1 indicates a wear-resistant coating formed according to the present invention on a substrate 2, e.g. any known mechanical component made of cast iron.
- Coating 1 comprises a first layer 3, preferably no more than 50 ⁇ m deep, formed of hard Cr, and characterized by being continuous, i.e. by presenting no detectable microcracks or porosity, and no inclusions of any sort.
- layer 3 On top of layer 3, there are deposited a given number (four in the example) of substantially identical layers 5a, 5b, 5c, 5d, each comprising a hard chromium matrix 6 in which are formed a number of microcracks 7 extending radially depthwise of layer 5 towards substrate 2, and a disperse phase in matrix 6 and consisting of a number of particles 8 of any hard nonmetal material.
- a first number of particles 8 is included in microcracks 7 of matrix 6, and a second number of particles 8 is embedded directly inside parts of matrix 6 with no microcracks 7; and the microcracks 7 of layers 5 deposited on first layer 3 are offset depthwise in relation to those of the adjacent layers 5.
- microcracks 7 of layer 5b extend depthwise towards underlying layer 5a and substantially towards the portions between microcracks 7 of layer 5a, i.e. towards matrix 6 portions of layer 5a presenting no microcracks.
- the microcracks 7 of each layer 5 present a "spiderweb" pattern along the interface surface 9 of each layer 5, as shown in Figure 5.
- the width of the microcracks, measured parallel to each layer 5, is at least 1 ⁇ m; the microcrack density measured at surfaces 9 ranges from 100 to 300 microcracks per centimeter of surface; and the size of nonmetal particles 8 ranges from 0.1 to 20 ⁇ m.
- a coating as described above may be formed electrolytically; layer 3 being formed by galvanically depositing Cr in known manner using any known chromium plating bath of the type resulting in no microcracks and containing no particles in suspension, or operating accordingly with a bath containing particles in suspension; and layers 5 being formed using known chromium plating baths of the type for forming microcracks and containing particles 8 in suspension.
- a further precaution to ensure layer 3 presents no microcracks is to limit its thickness, and to use such operating parameters (current cycles and density, etc.) as to limit the formation of stress within the layer due to excessive energy supply.
- the baths for forming layers 5 and containing particles 8 in suspension are preferably agitated at all times, e.g. by means of mechanical, fluidodynamics, energetic agitators, or by air injection.
- the nonmetal particles 8 included in the coating must be insoluble in the baths which present a chromic acid, sulphuric acid and catalyst base, are maintained at a temperature of about 55°C, and present a 20 to 400 gr/liter concentration of particles 8 (ranging in size between 0.1 and 20 micron).
- Particles 8 therefore consist of one or more materials in the group comprising: tungsten carbide, silicon carbide, chromium carbide, aluminium oxide, silicon nitride, boron carbide, diamond, graphite, hexagonal boron nitride.
- Each layer 5 may of course include particles 8 all of the same material or of different materials, and likewise from one layer to another.
- the cathode current supply cycle comprises the following steps:
- a bath with the following composition is prepared: CrO 3 250.0 gr/lt; FeSiF 6 1.5 gr/lt; H 2 SO 4 2.5 gr/lt SiC 50.0 gr/lt;
- Lead anodes and a cathode consisting of rings of lamellar cast iron are immersed in the bath, and a chromium coating is deposited, agitating the bath by recirculating roughly 300 lt/min and injecting air at roughly 5 bar pressure, and operating with a potential difference of 15 volts and a continuous cathode current of a mean density of 70 A per square decimeter, which is varied during deposition according to the following cycle:
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Electroplating Methods And Accessories (AREA)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| ITTO940101 | 1994-02-18 | ||
| IT94TO000101A IT1267394B1 (it) | 1994-02-18 | 1994-02-18 | Procedimento per la realizzazione di riporti galvanici compositi in cromo duro con una fase dispersa e riporto anti-usura realizzato con |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| EP0668375A1 EP0668375A1 (en) | 1995-08-23 |
| EP0668375B1 true EP0668375B1 (en) | 1999-01-13 |
Family
ID=11412164
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP95102258A Expired - Lifetime EP0668375B1 (en) | 1994-02-18 | 1995-02-17 | Process for forming composite galvanic coatings of hard chromium with a disperse phase, and wear-resistant coating formed thereby |
Country Status (3)
| Country | Link |
|---|---|
| EP (1) | EP0668375B1 (it) |
| DE (1) | DE69507172T2 (it) |
| IT (1) | IT1267394B1 (it) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19931829A1 (de) * | 1999-07-08 | 2001-01-18 | Federal Mogul Burscheid Gmbh | Galvanische Hartchromschicht |
| DE102007050811A1 (de) * | 2007-10-24 | 2009-04-30 | Robert Bosch Gmbh | Verschleißschutzschicht sowie Verfahren zu ihrer Herstellung |
| CN1764745B (zh) * | 2004-01-30 | 2012-01-11 | 株式会社理研 | 复合铬电镀膜及具有该膜的滑动件以及该滑动件的制备方法 |
| KR101589892B1 (ko) | 2008-04-04 | 2016-01-27 | 페데랄-모굴 부르샤이트 게엠베하 | 구조화된 크롬 고체 입자들 층 및 이의 제조 방법 |
Families Citing this family (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE69711722T2 (de) * | 1996-11-11 | 2002-08-08 | Teikoku Piston Ring Co Ltd | Galvanische Komposit-Chrom-Beschichtung und damit beschichtetes Gleitteil |
| EP0841414B2 (en) † | 1996-11-11 | 2005-03-02 | Teikoku Piston Ring Co., LTd. | Composite chromium plating film and sliding member covered thereof |
| DE19745811C2 (de) * | 1997-10-16 | 2002-06-13 | Federal Mogul Burscheid Gmbh | Galvanische Hartchromschicht, Verwendung und Verfahren zu deren Herstellung |
| SE514700C2 (sv) | 1999-03-19 | 2001-04-02 | Daros Holding Ab | Elektrolytisk beläggning av ett substrat med ett keramkromskikt, keramkromskikt samt kolvring |
| US20020197504A1 (en) * | 1999-12-27 | 2002-12-26 | Hiroyuki Takamura | Sliding member |
| JP4059621B2 (ja) * | 2000-09-29 | 2008-03-12 | 日本ピストンリング株式会社 | クロムめっき摺動部材及びその製造方法 |
| SE521471C2 (sv) | 2001-03-27 | 2003-11-04 | Koncentra Holding Ab | Kolvring och beläggning på en kolvring innefattande ett kompositmaterial av en keram och en intermetallisk förening |
| DE10255853A1 (de) | 2002-11-29 | 2004-06-17 | Federal-Mogul Burscheid Gmbh | Herstellung strukturierter Hartchromschichten |
| DE102004019370B3 (de) | 2004-04-21 | 2005-09-01 | Federal-Mogul Burscheid Gmbh | Herstellung einer strukturierten Hartchromschicht und Herstellung einer Beschichtung |
| DE102005023627B4 (de) * | 2005-05-21 | 2010-05-06 | Federal-Mogul Burscheid Gmbh | Stahlkolbering |
| DE102007037778A1 (de) * | 2007-08-10 | 2009-02-12 | Mahle International Gmbh | Hartchromschicht, beschichtetes Substrat und tribologisches System |
| JP5885207B2 (ja) | 2010-12-27 | 2016-03-15 | 日本ピストンリング株式会社 | 複合クロムめっき皮膜及びこの皮膜を用いた摺動部材 |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3531410A1 (de) * | 1985-09-03 | 1987-03-05 | Goetze Ag | Galvanische hartchromschicht |
| DE3933896C1 (it) * | 1989-10-11 | 1990-10-11 | Lpw-Chemie Gmbh, 4040 Neuss, De |
-
1994
- 1994-02-18 IT IT94TO000101A patent/IT1267394B1/it active IP Right Grant
-
1995
- 1995-02-17 EP EP95102258A patent/EP0668375B1/en not_active Expired - Lifetime
- 1995-02-17 DE DE69507172T patent/DE69507172T2/de not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19931829A1 (de) * | 1999-07-08 | 2001-01-18 | Federal Mogul Burscheid Gmbh | Galvanische Hartchromschicht |
| CN1764745B (zh) * | 2004-01-30 | 2012-01-11 | 株式会社理研 | 复合铬电镀膜及具有该膜的滑动件以及该滑动件的制备方法 |
| DE102007050811A1 (de) * | 2007-10-24 | 2009-04-30 | Robert Bosch Gmbh | Verschleißschutzschicht sowie Verfahren zu ihrer Herstellung |
| KR101589892B1 (ko) | 2008-04-04 | 2016-01-27 | 페데랄-모굴 부르샤이트 게엠베하 | 구조화된 크롬 고체 입자들 층 및 이의 제조 방법 |
Also Published As
| Publication number | Publication date |
|---|---|
| DE69507172T2 (de) | 1999-07-22 |
| EP0668375A1 (en) | 1995-08-23 |
| ITTO940101A0 (it) | 1994-02-18 |
| IT1267394B1 (it) | 1997-02-05 |
| ITTO940101A1 (it) | 1995-08-18 |
| DE69507172D1 (de) | 1999-02-25 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP0668375B1 (en) | Process for forming composite galvanic coatings of hard chromium with a disperse phase, and wear-resistant coating formed thereby | |
| Aal et al. | Enhancement of wear resistance of ductile cast iron by Ni–SiC composite coating | |
| Sohi et al. | Comparative tribological study of hard and crack-free electrodeposited chromium coatings | |
| KR101153048B1 (ko) | 철-인 전기 도금 전해조 및 방법 | |
| EP1719827B1 (en) | Composite chromium plating film and sliding member having the same and its production method | |
| US6503642B1 (en) | Hard-chrome plated layer | |
| KR102638615B1 (ko) | 크롬계 코팅물, 크롬계 코팅물 제조 방법, 및 코팅된 물체 | |
| KR20110008027A (ko) | 구조화된 크롬 고체 입자들 층 및 이의 제조 방법 | |
| US20050112399A1 (en) | Erosion resistant coatings and methods thereof | |
| US9850587B2 (en) | Hard composite chromium plating film and sliding member coated with such film | |
| US10428437B2 (en) | Wear-resistant coating produced by electrodeposition and process therefor | |
| US6354358B1 (en) | Continuous casting mold with tungsten alloy plating and method of producing the same | |
| CN103184457B (zh) | 一种表面合金化强化方法 | |
| Rajih et al. | Investigation some properties of (Zn-Ni-SiC) composites coating on low carbon steel | |
| Karakurkchi et al. | Determining features of application of functional electrochemical coatings in technologies of surface treatment | |
| CN1255579C (zh) | 钛合金表面原位生长高硬度耐磨陶瓷涂层方法 | |
| JPH02217497A (ja) | ニッケル―タングステン―炭化珪素複合めっき法 | |
| Kir et al. | Effect of hard chrome plating parameters on the wear resistance of low carbon steel | |
| Abdel Hamid et al. | Electrodeposition and characterization of chromium–tungsten carbide composite coatings from a trivalent chromium bath | |
| EP0147484B1 (en) | A process for obtaining a protective coating for surfaces subjected to mechanical and thermal wear, and coating obtained by such process | |
| EP0679736B1 (en) | Improvement of properties of the surface of a titanium alloy engine valve | |
| Wilson et al. | Development and characteristics of crack-free chromium coatings produced by electroplating | |
| Bapui | Electrodeposition and characterization of nickel-molybdenum disulfide composites | |
| Ibrahim et al. | Enhanced wear resistance of cast ductile iron by Ni-SiC composite coating | |
| Huang et al. | Properties of Cr–C–Al 2 O 3 Deposits Prepared on a Cu Substrate Using Cr 3+-Based Plating Baths |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
| AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): DE GB NL |
|
| 17P | Request for examination filed |
Effective date: 19951130 |
|
| 17Q | First examination report despatched |
Effective date: 19961011 |
|
| GRAG | Despatch of communication of intention to grant |
Free format text: ORIGINAL CODE: EPIDOS AGRA |
|
| GRAG | Despatch of communication of intention to grant |
Free format text: ORIGINAL CODE: EPIDOS AGRA |
|
| GRAG | Despatch of communication of intention to grant |
Free format text: ORIGINAL CODE: EPIDOS AGRA |
|
| GRAH | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOS IGRA |
|
| GRAH | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOS IGRA |
|
| GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
| AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): DE GB NL |
|
| REF | Corresponds to: |
Ref document number: 69507172 Country of ref document: DE Date of ref document: 19990225 |
|
| PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
| STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
| 26N | No opposition filed | ||
| REG | Reference to a national code |
Ref country code: GB Ref legal event code: IF02 |
|
| REG | Reference to a national code |
Ref country code: GB Ref legal event code: 732E |
|
| NLS | Nl: assignments of ep-patents |
Owner name: KONCENTRA HOLDING AB |
|
| NLT1 | Nl: modifications of names registered in virtue of documents presented to the patent office pursuant to art. 16 a, paragraph 1 |
Owner name: KONCENTRA MARINE & POWER AB |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: NL Payment date: 20090204 Year of fee payment: 15 Ref country code: DE Payment date: 20090205 Year of fee payment: 15 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: GB Payment date: 20090204 Year of fee payment: 15 |
|
| REG | Reference to a national code |
Ref country code: NL Ref legal event code: V1 Effective date: 20100901 |
|
| GBPC | Gb: european patent ceased through non-payment of renewal fee |
Effective date: 20100217 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: NL Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20100901 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20100901 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GB Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20100217 |