EP0005285B1 - Process for applying a dense layer of cermets or cemented carbides to a metal object - Google Patents
Process for applying a dense layer of cermets or cemented carbides to a metal object Download PDFInfo
- Publication number
- EP0005285B1 EP0005285B1 EP79200170A EP79200170A EP0005285B1 EP 0005285 B1 EP0005285 B1 EP 0005285B1 EP 79200170 A EP79200170 A EP 79200170A EP 79200170 A EP79200170 A EP 79200170A EP 0005285 B1 EP0005285 B1 EP 0005285B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- layer
- sprayed
- cermets
- metal
- pressure
- 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
Links
- 229910052751 metal Inorganic materials 0.000 title claims description 29
- 239000002184 metal Substances 0.000 title claims description 29
- 238000000034 method Methods 0.000 title claims description 18
- 150000001247 metal acetylides Chemical class 0.000 title claims description 7
- 239000010410 layer Substances 0.000 claims description 42
- 239000011230 binding agent Substances 0.000 claims description 15
- 239000000463 material Substances 0.000 claims description 12
- 239000002245 particle Substances 0.000 claims description 9
- 238000007596 consolidation process Methods 0.000 claims description 7
- 238000005507 spraying Methods 0.000 claims description 7
- 229910017052 cobalt Inorganic materials 0.000 claims description 5
- 239000010941 cobalt Substances 0.000 claims description 5
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims description 5
- 239000000203 mixture Substances 0.000 claims description 5
- UONOETXJSWQNOL-UHFFFAOYSA-N tungsten carbide Chemical compound [W+]#[C-] UONOETXJSWQNOL-UHFFFAOYSA-N 0.000 claims description 4
- 239000000843 powder Substances 0.000 claims description 3
- 239000000919 ceramic Substances 0.000 claims description 2
- 239000011247 coating layer Substances 0.000 claims description 2
- 238000005336 cracking Methods 0.000 claims description 2
- 238000005056 compaction Methods 0.000 description 4
- PXHVJJICTQNCMI-UHFFFAOYSA-N nickel Substances [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 4
- 229910010293 ceramic material Inorganic materials 0.000 description 3
- 239000011248 coating agent Substances 0.000 description 3
- 238000000576 coating method Methods 0.000 description 3
- 150000002739 metals Chemical class 0.000 description 3
- 229910052759 nickel Inorganic materials 0.000 description 3
- 238000003466 welding Methods 0.000 description 3
- 229910045601 alloy Inorganic materials 0.000 description 2
- 239000000956 alloy Substances 0.000 description 2
- 239000011195 cermet Substances 0.000 description 2
- 229910052804 chromium Inorganic materials 0.000 description 2
- 239000011651 chromium Substances 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 238000009792 diffusion process Methods 0.000 description 2
- 238000010285 flame spraying Methods 0.000 description 2
- 230000004927 fusion Effects 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 238000007750 plasma spraying Methods 0.000 description 2
- 238000005245 sintering Methods 0.000 description 2
- 239000010937 tungsten Substances 0.000 description 2
- 229910052721 tungsten Inorganic materials 0.000 description 2
- 229910000851 Alloy steel Inorganic materials 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000007731 hot pressing Methods 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 229910000623 nickel–chromium alloy Inorganic materials 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000012254 powdered material Substances 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 239000007790 solid phase Substances 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 230000008646 thermal stress Effects 0.000 description 1
- MTPVUVINMAGMJL-UHFFFAOYSA-N trimethyl(1,1,2,2,2-pentafluoroethyl)silane Chemical compound C[Si](C)(C)C(F)(F)C(F)(F)F MTPVUVINMAGMJL-UHFFFAOYSA-N 0.000 description 1
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 1
- -1 tungsten carbides Chemical class 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- 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
- C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
- C23C4/18—After-treatment
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/12—Both compacting and sintering
- B22F3/1208—Containers or coating used therefor
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- 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
- C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
- C23C4/04—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge characterised by the coating material
- C23C4/06—Metallic material
Definitions
- the invention relates to a process for applying a dense, hard and wear-resistant layer of cermets or cemented carbides to a metal object by spraying a powder material consisting of hard particles of cermets or cemented carbides, followed by consolidation of the sprayed-on layer at high temperature and pressure.
- British patent specification 1.451.113 discloses a process for spraying a layer on a metal object, such layer consisting of a metal or an alloy, which may contain ceramic materials (so-called cermets).
- cermets ceramic materials
- spraying by known methods, for example flame spraying or plasma spraying of powdered materials, a porous layer is obtained.
- the adhesion of this layer to the base material is found unsatisfactory, and therefore the said patent specification recommends consolidating the porous layer by fusing the binder metal present therein under vacuum, thus reducing the porosity. To combat oxidation, this fusion is carried out under vacuum.
- good results are obtained by this method if the layer consists of 50 percent by weight of tungsten carbide in a matrix of a nickel-chromium alloy serving as binder metal.
- binder metal in the layer decreases, and the content of hard particles accordingly increases, it seems to become more and more difficult to consolidate the layer by fusing the binder metal, and at a binder metal content of 30 percent or less, it becomes practically impossible.
- DE - A - 1.783.061 proposes application of a comparable dense layer by built-up welding, using a tubular or rod welding electrode containing a binder metal and tungsten carbides.
- a tubular or rod welding electrode containing a binder metal and tungsten carbides.
- Such an electrode preferably contains 30-40 percent by weight of binder metal and 70-60 percent by weight of carbide particles. During welding, this material is further mingled with some quantity of molten base material.
- the binder metal must contain at least one of the metals Co, Ni, Fe or Cr as chief constituent.
- the layer consists of more than 70 percent by weight of ceramic particles, such as hard metal carbides, for example tungsten or titanium carbide, or other hard materials.
- ceramic particles such as hard metal carbides, for example tungsten or titanium carbide, or other hard materials.
- a cohesive and/or adhesive bond cannot be improved by internal fusion.
- the consolidation of the sprayed-on porous layer is accomplished by isostatic compaction at a temperature of at least 1000°C and a pressure of at least 1000 bars, for at least one half hour, whereby said binder metal is not melted.
- British Patent specification 1.367.762 discloses a method to form a sprayed-on cermet coating on a surface of a thin metal sheet whereby both coating and substrate are subjected to hot pressing or sintering. According to this method pressing is executed from one side or opposite sides of the metal sheet; therefore this method is not suitable when more, e.g. rounded sides of a body have to be processed with improved layers in one step.
- the process according the invention is especially suitable for applying a layer of tungsten carbide/cobalt to a forged, cast or sintered core or similar base material
- Cermets or other metals or ceramic materials may alternatively be used, for example TiC or Si 2 N 4 .
- binder metal a metal or an alloy consisting predominantly of Ni, Co, Fe or Cr may be used.
- cobalt or an a!!oy of cobalt and nickel is used. The proper choice of course depends partly on the base material used, to which the applied layer must bond well.
- the layer is applied by spraying on of a powder mixture containing the binder metal and the particles in the desired proportion for the layer.
- This spraying may be carried out in conventional manner, for example by flame spraying or plasma spraying, a porous layer being formed in either case.
- the objects may be completely or only partly coated with the sprayed layer.
- the coating material may be applied in one or several steps. If desired, the successive layers may differ from each other in composition.
- the surface may then be finished smooth. In most cases, however, this can be omitted because the roughness of the surface after consolidation is chiefly determined by the grain size of the pressure transmitting medium. If the proper grain size is used, the smoothness of the surface will be sufficient in most cases even without finishing. A grain size of 0.10-0.25 mm is very satisfactory for many purposes.
- a mixture containing at least 7 percent by weight of cermet particles is used for the sprayed-on layer, and preferably a mixture consisting of 83-94 percent by weight of tungsten carbide, remainder cobalt.
- the thermal expension coefficients of cermets or cemented carbides differ appreciably from those of metals.
- FIG. 1 schematically representing an object produced according to the invention
- Fig. 2 and 3 showing photographs of a compacted layer before and after the hot isostatic compaction.
- the coated object 3 is placed in a comparatively thin-walled holder 2, for example of low-alloy steel. Then the holder is completely filled with a pressure transmitting medium 5 and closed gastight with a cover 1. Then the holder 2 is placed in a hot isostatic press (not shown) in which the holder is heated to the consolidating temperature, which is at least 1000°C, preferably 1000-1400°C. The temperature during this operation is always such that the consolidation takes place in the solid phase. At this temperature the binder metal does not melt, but some sintering does occur. Simultaneously with the raising of the temperature, or after the desired temperature has been reached, the gas pressure in the press is raised to at least 1000 bars, preferably up to 1800 bars.
- Fig. 2 shows a photograph of a plasma- sprayed layer 4A on a base material 3A before hot isostatic compaction.
- Fig. 3 is a photograph taken after hot isostatic compaction and shows that 1) layer 4 has attained maximum density, 2) an optimum diffusion bond 6 has been formed between 3 and 4.
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Plasma & Fusion (AREA)
- Physics & Mathematics (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Manufacturing & Machinery (AREA)
- Coating By Spraying Or Casting (AREA)
- Other Surface Treatments For Metallic Materials (AREA)
- Powder Metallurgy (AREA)
- Ceramic Capacitors (AREA)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
NL7804454 | 1978-04-26 | ||
NL7804454A NL7804454A (nl) | 1978-04-26 | 1978-04-26 | Werkwijze om op een metalen voorwerp een dichte laag hardmetaal of cermets aan te brengen. |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0005285A1 EP0005285A1 (en) | 1979-11-14 |
EP0005285B1 true EP0005285B1 (en) | 1982-03-17 |
Family
ID=19830731
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP79200170A Expired EP0005285B1 (en) | 1978-04-26 | 1979-04-09 | Process for applying a dense layer of cermets or cemented carbides to a metal object |
Country Status (9)
Country | Link |
---|---|
EP (1) | EP0005285B1 (enrdf_load_stackoverflow) |
JP (1) | JPS54142220A (enrdf_load_stackoverflow) |
AU (1) | AU528527B2 (enrdf_load_stackoverflow) |
CA (1) | CA1124586A (enrdf_load_stackoverflow) |
DE (1) | DE2962269D1 (enrdf_load_stackoverflow) |
MX (1) | MX151789A (enrdf_load_stackoverflow) |
NL (1) | NL7804454A (enrdf_load_stackoverflow) |
NO (1) | NO153694C (enrdf_load_stackoverflow) |
ZA (1) | ZA791582B (enrdf_load_stackoverflow) |
Families Citing this family (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
NL7905973A (nl) * | 1979-08-03 | 1981-02-05 | Skf Ind Trading & Dev | Werkwijze voor het aanbrengen van een dichte, harde, hechte en slijtvaste laag van cermets of keramisch materiaal op een metalen voorwerp en aldus verkregen voorwerp. |
NL7908745A (nl) * | 1979-12-04 | 1981-07-01 | Skf Ind Trading & Dev | Werkwijze voor het vervaardigen van een voorwerp, waarop door thermisch opspuiten een buitenlaag wordt aangebracht en voorwerp, in het bijzonder een boor- beitel, verkregen volgens deze werkwijze. |
JPS60215754A (ja) * | 1984-04-11 | 1985-10-29 | Nippon Kokan Kk <Nkk> | 高硬度溶射層の製造方法 |
US4996119A (en) * | 1984-08-27 | 1991-02-26 | Kabushiki Kaisha Kenwood | Speaker cone plate and method of forming |
JPS61257402A (ja) * | 1984-12-25 | 1986-11-14 | Namekawa Tatsuo | 金属中空異形品の内面成形方法 |
US4603062A (en) * | 1985-01-07 | 1986-07-29 | Cdp, Ltd. | Pump liners and a method of cladding the same |
JPS61201786A (ja) * | 1985-03-04 | 1986-09-06 | Nippon Telegr & Teleph Corp <Ntt> | 材料の表面処理方法 |
JPH0778273B2 (ja) * | 1987-11-27 | 1995-08-23 | トーカロ株式会社 | 翼部材の表面処理方法 |
DE3814362C1 (en) * | 1988-04-28 | 1989-12-07 | Thyssen Guss Ag, 4330 Muelheim, De | Process for producing bucket tappets and similarly stressed components in internal combustion engines |
US4978487A (en) * | 1989-01-13 | 1990-12-18 | Westinghouse Electric Corp. | Method of treating a coating on a reactor coolant pump sealing surface |
US5057340A (en) * | 1990-04-20 | 1991-10-15 | Westinghouse Electric Corp. | Method of forming a coating on a reactor coolant pump sealing surface |
DE69105623T2 (de) * | 1990-05-10 | 1995-04-20 | Apv Corp Ltd | Verfahren zum Aufbringen einer Beschichtung auf einem Metall oder einen Verbundwerkstoff. |
US7043819B1 (en) * | 1996-12-23 | 2006-05-16 | Recast Airfoil Group | Methods for forming metal parts having superior surface characteristics |
WO1999023272A1 (de) * | 1997-11-03 | 1999-05-14 | Siemens Aktiengesellschaft | Verfahren zur herstellung einer schutzschicht auf einem für eine heissgasbeaufschlagung ausgelegten grundkörper und ausgelegtes erzeugnis |
CN103143699B (zh) * | 2013-03-07 | 2015-03-11 | 南通高欣金属陶瓷复合材料有限公司 | 金属-陶瓷预制件复合增强耐磨件及其制备方法 |
CN119120975A (zh) * | 2024-07-26 | 2024-12-13 | 江苏耀龙机械制造有限公司 | 一种抗氧化致密复式碳化钨基稀有金属陶瓷及其制备方法 |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR1434158A (fr) * | 1964-11-25 | 1966-04-08 | Sfec | Perfectionnements aux revêtements protecteurs réfractaires, et procédé de fabrication de ces éléments |
NL6709916A (enrdf_load_stackoverflow) * | 1967-07-17 | 1968-11-25 | ||
GB1367762A (en) * | 1971-09-17 | 1974-09-25 | Ass Eng Ltd | cermet materials |
-
1978
- 1978-04-26 NL NL7804454A patent/NL7804454A/xx not_active Application Discontinuation
-
1979
- 1979-04-03 ZA ZA791582A patent/ZA791582B/xx unknown
- 1979-04-06 AU AU45891/79A patent/AU528527B2/en not_active Expired
- 1979-04-09 DE DE7979200170T patent/DE2962269D1/de not_active Expired
- 1979-04-09 EP EP79200170A patent/EP0005285B1/en not_active Expired
- 1979-04-24 JP JP4982279A patent/JPS54142220A/ja active Granted
- 1979-04-25 NO NO791368A patent/NO153694C/no unknown
- 1979-04-25 MX MX177433A patent/MX151789A/es unknown
- 1979-04-26 CA CA326,420A patent/CA1124586A/en not_active Expired
Also Published As
Publication number | Publication date |
---|---|
JPS54142220A (en) | 1979-11-06 |
CA1124586A (en) | 1982-06-01 |
JPS636630B2 (enrdf_load_stackoverflow) | 1988-02-10 |
NO153694C (no) | 1986-05-07 |
EP0005285A1 (en) | 1979-11-14 |
AU4589179A (en) | 1979-11-29 |
ZA791582B (en) | 1980-04-30 |
AU528527B2 (en) | 1983-05-05 |
NO791368L (no) | 1979-10-29 |
NL7804454A (nl) | 1979-10-30 |
NO153694B (no) | 1986-01-27 |
MX151789A (es) | 1985-03-18 |
DE2962269D1 (en) | 1982-04-15 |
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