EP0304488A1 - Procede pour l'enrobage des pieces - Google Patents

Procede pour l'enrobage des pieces Download PDF

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Publication number
EP0304488A1
EP0304488A1 EP87903473A EP87903473A EP0304488A1 EP 0304488 A1 EP0304488 A1 EP 0304488A1 EP 87903473 A EP87903473 A EP 87903473A EP 87903473 A EP87903473 A EP 87903473A EP 0304488 A1 EP0304488 A1 EP 0304488A1
Authority
EP
European Patent Office
Prior art keywords
coating
workpiece
workpieces
refractory
dispersion
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.)
Withdrawn
Application number
EP87903473A
Other languages
German (de)
English (en)
Other versions
EP0304488A4 (fr
Inventor
Valentin Petrovich Nechaev
Valery Ivanovich Akhmatov
Gennady Ivanovich Bobryakov
Boris Alexeevich Pepelin
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
NAUCHNO-ISSLEDOVATELSKY INSTITUT TEKHNOLOGII AVTOMOBILNOI PROMYSHLENNOSTI (NIITavtoprom)
Original Assignee
NAUCHNO-ISSLEDOVATELSKY INSTITUT TEKHNOLOGII AVTOMOBILNOI PROMYSHLENNOSTI (NIITavtoprom)
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by NAUCHNO-ISSLEDOVATELSKY INSTITUT TEKHNOLOGII AVTOMOBILNOI PROMYSHLENNOSTI (NIITavtoprom) filed Critical NAUCHNO-ISSLEDOVATELSKY INSTITUT TEKHNOLOGII AVTOMOBILNOI PROMYSHLENNOSTI (NIITavtoprom)
Publication of EP0304488A1 publication Critical patent/EP0304488A1/fr
Publication of EP0304488A4 publication Critical patent/EP0304488A4/fr
Withdrawn legal-status Critical Current

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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
    • 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
    • C23C26/00—Coating not provided for in groups C23C2/00 - C23C24/00
    • C23C26/02—Coating not provided for in groups C23C2/00 - C23C24/00 applying molten material to the substrate

Definitions

  • the present invention relates to the processing of materials in a non-mechanical way and relates to a method for producing a coating on workpieces.
  • the known method for producing a coating is carried out by a on a preferably made of cast iron or steel workpiece from powdery self-ing alloys of the Ni-B-Si (nickel-boron-silicon) system with solidifying additives on carbides, for example on Cr , B, W (chrome, boron, tungsten) existing coating material applied, uz is made by flame spraying.
  • Ni-B-Si nickel-boron-silicon
  • the workpiece with the applied coating is heated to the melting temperature of the coating to increase the adhesive strength of the materials of the coating and the workpiece by placing it in a salt bath, e.g. Barium salt bath, which has been preheated to a temperature at least 50 ° C. above the melting temperature of the coating material, is immersed and held at this temperature for 1 to 3 minutes and then removed from the bath and cooled.
  • a salt bath e.g. Barium salt bath
  • the coating By immersing the workpiece with the applied coating in a salt bath, the coating can be melted, its density increased compared to the density when sprayed on, and its adhesive strength with the workpiece can be increased.
  • the salt crust is removed from the workpiece surface. If the salt crust is not completely removed, occurs intercrystalline corrosion on workpiece sections not protected by the coating.
  • the workpiece When carrying out the known method for producing a coating, the workpiece cannot be fixed rigidly over its entire length for the purpose of melting the coating; this applies in particular to long-dimensioned and thin-walled workpieces and workpieces of complex shape.
  • the holding time required for the complete melting of the coating material can only be determined with difficulty.
  • Holding the workpiece with the applied coating in the salt bath for a not sufficiently long time leads to an incomplete melting of the coating material, that is to say the melting does not take place in the entire thickness of the coating layer, while the holding takes place within an optimum time to flow off Part of the mass of the molten coating leads.
  • the present invention has for its object to develop a method for producing a coating on workpieces, which ensures the production of high-quality coatings without deformation of thin-walled and long-dimensioned workpieces of complicated shape.
  • This object is achieved in that, in a method for the production of coatings on workpieces, consisting in that a coating material is applied to the workpiece surface, which is heated and cooled until it melts, the workpiece according to the invention before the coating melts into a powdered refractory is introduced, which is compacted for the purpose of determining the workpiece and the melting of the coating is carried out therein, after which the workpiece is held at the melting temperature of the coating until a diffusion zone is formed between the materials of the coating and the workpiece, while cooling in the powdery refractory to for crystal precipitation of the coating material takes place.
  • the workpiece with the applied coating is securely fixed with the most available and inexpensive means.
  • the powdery refractory makes it safe Detection of workpieces of any shape and with any coating material applied guaranteed. This happens because the compacted powdered refractory lies tightly on the entire workpiece surface, even when there are cavities and various projections and depressions on the workpiece.
  • the workpiece with the applied coating which is determined in such a manner, is not exposed to any risk of warping during heating until the coating melts.
  • the stresses accumulated during the production or during the earlier use of this workpiece are distributed evenly in the workpiece volume without deforming it.
  • the workpieces with the applied coating can be kept within a time beyond which the coating does not flow off, because the powdered refractory lies tightly against the workpiece with the applied coating Prevents the coating from flowing off.
  • the workpiece is not exposed to any risk of warping.
  • a powdered refractory that contains a mixture consisting of two fractions with different degrees of dispersion: 60 to 90% by mass of powder with a degree of dispersion of 0.1 to 0.7 mm and 40 to 10% by mass of powder with a degree of dispersion of Represents 0.01 to 0.06 mm.
  • the use of the powdered refractory with the above-mentioned composition of the fractions of different degrees of dispersion enables the powdered refractory to be compressed to a predetermined degree. As a result, the workpiece with the applied coating can be reliably identified.
  • the reliability decreases when the workpiece is fixed with the applied coating before it melts.
  • the size of the powder particles is less than 0.1 mm, which is taken in a ratio of 60 to 90% by mass, the powdered refractory is compressed evenly over the entire volume. difficult because of the tendency of the particles to spontaneously stick together.
  • the maximum possible compression over the entire volume of the powdered refractory material is not achieved because the volume the voids between the larger particles are larger than the volume of the fine particles.
  • these substances can be used several times in production.
  • the pouring properties of the above-mentioned powdered refractories allow these substances to be poured in with a preliminary high density. This helps to ensure that the workpieces are securely fixed during the melting of the coating.
  • the powdery refractory material is expediently compressed to a density of 1.65 to 2.8 g / cm 3.
  • the compaction of the named substance in the range of the density values given above is the most favorable for the selected group of substances such as quartz sand, powdered chamotte, zirconium concentrate, whereby the workpiece with the applied coating can be determined with the maximum possible certainty.
  • the powdered refractory material is compacted below a density of 1.65 g / cm 3 , the security of the workpiece with the applied coating is reduced. In addition, the workpiece is exposed to a greater risk of warping when it is heated until the coating melts, and the ability of the compressed powdered refractory to prevent the melted coating material from flowing away decreases.
  • the powdered refractory is expediently vibrated at a vibration frequency of 6 compressed to 8 Hz.
  • the compression of the powdered refractory material by vibration in the specified range of vibration frequencies allows the workpiece with the applied coating to be securely fixed when using the powdered refractory from the selected group of substances.
  • Compression with a vibration frequency above 8 Hz affects the effectiveness of the compression process because the mechanical vibrations generated in the powdered refractory tend to decay. This increases the compaction time and reduces the ability of the powdered refractory to securely hold the workpiece with the applied coating.
  • the method according to the invention for producing a coating on workpieces achieves a high-quality coating on workpieces of complicated shape, in particular on long-dimensioned and thin-walled workpieces.
  • the workpieces When carrying out the method according to the invention for producing a coating on workpieces, the workpieces are not deformed and are not exposed to a risk of warping; this applies in particular to long-gauge and thin-walled workpieces.
  • the cover is made with a predetermined thickness, according to which the workpieces require only minor mechanical processing.
  • the adhesive strength of the coating materials and the workpiece is practically the same as the breaking strength of an aluminum casting.
  • the method according to the invention for producing a coating on workpieces is carried out fairly simply and does not require complicated equipment and bottleneck materials.
  • Fig. I a filled with a powdered refractory material container containing a workpiece accommodated therein with Uberzug-applied, for carrying out the inventive method for Her - position of a train on Uber workpieces shown.
  • the method according to the invention is carried out as follows.
  • a thin-walled long workpiece is prepared for spraying, etc. the surfaces to be coated are subjected to a rough mechanical treatment for the purpose of removing oxide skins and producing a micro-roughness which promotes the adhesion of the coating to the workpiece.
  • the workpiece 1 is placed in a rotating device (not shown) of a known construction and the material of the coating 2 is applied with a predetermined thickness and shape by spraying on under the action of heat, optionally by flame spraying, which is well known to most experts.
  • a container 3 which has the shape of a cup, arranged along its longitudinal geometrical vertical axis 3a so that the lower part of the workpiece 1 is at a distance from the inner surface of the bottom of the Container 3 is located, while the outer side surfaces of the workpiece 1 with a margin relative to the inner side surface of the container ters 3 come to rest.
  • the clearance between the outer surfaces of the workpiece 1 and the inner wall surfaces of the container 3 is filled with a powdered refractory 4, part of which is previously poured onto the bottom of the container 3 to hold the workpiece 1.
  • the substance 4 is compacted for the purpose of making the workpiece free. Thereafter, the container 3 with the workpiece 1 ascertained by the compacted substance 4 is introduced into an oven (not shown) of any known construction suitable for this purpose.
  • the heating can be done in another way, e.g. be made by means of an induction coil.
  • the container 3, the workpiece 1 with the cover 2 and the material 4 are heated until the material of the cover 2 melts.
  • the workpiece 1 is then held at the melting temperature of the coating to form a diffusion zone lying between the materials of the coating 2 and the workpiece 1.
  • the holding time is determined experimentally.
  • the diffusion zone forms at the expense of a counter-diffusion of the material of the coating 2 and the material of the workpiece 1 and represents a layer of an intermediate good with the physical-mechanical properties lying between the properties of the material of the coating 2 and the material of the workpiece 1. Thanks to the presence This zone ensures a high adhesive strength of the coating with the workpiece 1 and a high operability of this coating.
  • the container 3 with the workpiece 1 and the substance 4 is cooled until the substance of the coating 2 crystallizes, as a result of which the predetermined shape of the coating 2 on the workpiece 1 is retained.
  • the workpiece 1 is then subjected to mechanical processing until the required dimensions are reached.
  • a coating 2 made of a widely known alloy of the "Kolmonoi" type is applied by flame spraying.
  • control shaft 1 is placed in a container 3, in the quartz sand 4, which is a mixture of two fractions of different degrees of dispersion, etc. Represents 60% by mass of powder with a degree of dispersion of 0.2 mm and 40% by mass of powder with a degree of dispersion of 0.01 mm.
  • the quartz sand is then compacted by vibration with a vibration frequency of 6 Hz until a density of 1.65 g / cm 3 is reached .
  • control shaft 1 is then held at a melting temperature of 1100 ° C. and cooled until the crystal of the coating material has precipitated, as described above.
  • control shaft 1 After cooling to room temperature, the control shaft 1 is removed from the container 3 and subjected to a final mechanical processing.
  • a control shaft 1 made of high-strength cast iron is introduced into a container 3 after the preparation of its surface and the application of the coating material, as described above.
  • a powdered refractory 4 uz quartz sand with additives to powder is in the container 3 miger chamotte, which is a mixture of two fractions of different degrees of dispersion: 80 mass% powder with 0.1 mm degree of dispersion and 20 mass% powder with 0.03 mm degree of dispersion poured.
  • the powdered refractory 4 is compacted by vibration at a frequency of 7 Hz until a density of 1.8 g / cm 3 is reached .
  • control shaft 1 with the applied coating 2 is heated in an oven until the coating 2 melts and held at 1100 ° C., after which it is cooled until the coating 2 crystallizes.
  • control shaft 1 After cooling to room temperature, the control shaft 1 is removed from the container 3 and subjected to a final mechanical processing.
  • a control shaft 1 made of high-strength cast iron with the coating 2 applied to it is introduced into a container 3, as described above.
  • Zircon concentrate 4 which is a mixture of two fractions with different degrees of dispersion: 90% by mass of powder with 0.7 mm degree of dispersion and 10% by mass of powder with 0.05 mm degree of dispersion.
  • the material of the coating 2 is introduced into a melting furnace, kept at 1100 ° C. and then until the Uberzuges 2 cooled.
  • control shaft 1 After cooling to room temperature, the control shaft 1 is removed from the container 3 and subjected to a final mechanical processing.
  • the deviation of the geometry of the workpiece over its length of 1200 mm was 0.1 to 0.3 mm after the coating had melted.
  • coatings by the process according to the invention are carried out using light and simple means, the coatings produced have reliable adhesion to workpieces and serve various purposes, such as increasing wear resistance, corrosion protection, strengthening, and the generation of friction or Sliding properties, etc
  • the method according to the invention for the production of coatings does not require the use of expensive special equipment for its implementation.
  • the present invention can be used particularly effectively for the production of coatings on thin-walled, long-dimensioned workpieces of complex shape.
  • the method according to the invention for the production of coatings on workpieces can be used in the manufacture of workpieces with any dimensions and any shape for the renewal of their worn or used parts while at the same time obtaining predetermined properties (friction, sliding properties, corrosion resistance, heat and heat resistance) .

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Plasma & Fusion (AREA)
  • Nitrogen And Oxygen Or Sulfur-Condensed Heterocyclic Ring Systems (AREA)
  • Application Of Or Painting With Fluid Materials (AREA)
  • Other Surface Treatments For Metallic Materials (AREA)

Abstract

Un procédé pour l'enrobage des pièces consiste à appliquer à la surface d'une pièce (1) un matériau d'enrobage (2). La pièce (1) revêtue de l'enrobage (2) est ensuite introduite dans un matériau réfractaire (4) qui est compacté afin de maintenir la pièce (1) et dans lequel on effectue la fusion dudit enrobage (2). La pièce (1) est maintenue à ladite température de fusion jusqu'à ce qu'une zone de diffusion intermédiaire soit obtenue entre le matériau d'enrobage (2) et celui de la pièce (1). Le refroidissement est réalisé à l'intérieur du matériau réfractaire (4) jusqu'à l'obtention de la cristallisation du matériau d'enrobage (2).
EP19870903473 1987-03-11 1987-03-11 Procede pour l'enrobage des pieces. Withdrawn EP0304488A4 (fr)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/SU1987/000028 WO1988007094A1 (fr) 1987-03-11 1987-03-11 Procede pour l'enrobage des pieces

Publications (2)

Publication Number Publication Date
EP0304488A1 true EP0304488A1 (fr) 1989-03-01
EP0304488A4 EP0304488A4 (fr) 1989-09-26

Family

ID=21617084

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19870903473 Withdrawn EP0304488A4 (fr) 1987-03-11 1987-03-11 Procede pour l'enrobage des pieces.

Country Status (4)

Country Link
EP (1) EP0304488A4 (fr)
JP (1) JPH01502595A (fr)
BR (1) BR8707695A (fr)
WO (1) WO1988007094A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19520149A1 (de) * 1995-06-01 1996-12-05 Bergmann Hans Wilhelm Endkonturnahes Laserstrahlbeschichten mit Kokille

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2991195A (en) * 1960-02-11 1961-07-04 Lockheed Aircraft Corp Method of metallizing holes and cavities with a refractory metal
FR2209854A1 (fr) * 1972-12-12 1974-07-05 Skf Ind Trading & Dev
EP0034408A1 (fr) * 1980-02-13 1981-08-26 Permelec Electrode Ltd Procédé pour former un revêtement anticorrosif sur un substrat métallique servant à un electrode
EP0092959A2 (fr) * 1982-04-23 1983-11-02 Exxon Research And Engineering Company Procédé de revêtement d'un substrat métallique avec un revêtement protecteur en aluminium-silicium, substrats métalliques ainsi revêtus et utilisation desdits substrats métalliques revêtus
WO1986002868A1 (fr) * 1984-11-09 1986-05-22 Micra Limited Instruments chirurgicaux d'incision

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA1067354A (fr) * 1975-04-11 1979-12-04 Frederick T. Jaeger Revetement de tube bouilleur et methode de pose
CH664378A5 (de) * 1984-12-18 1988-02-29 Castolin Sa Verfahren zum einschmelzen einer metallischen oberflaechenschicht auf einem werkstueck.

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2991195A (en) * 1960-02-11 1961-07-04 Lockheed Aircraft Corp Method of metallizing holes and cavities with a refractory metal
FR2209854A1 (fr) * 1972-12-12 1974-07-05 Skf Ind Trading & Dev
EP0034408A1 (fr) * 1980-02-13 1981-08-26 Permelec Electrode Ltd Procédé pour former un revêtement anticorrosif sur un substrat métallique servant à un electrode
EP0092959A2 (fr) * 1982-04-23 1983-11-02 Exxon Research And Engineering Company Procédé de revêtement d'un substrat métallique avec un revêtement protecteur en aluminium-silicium, substrats métalliques ainsi revêtus et utilisation desdits substrats métalliques revêtus
WO1986002868A1 (fr) * 1984-11-09 1986-05-22 Micra Limited Instruments chirurgicaux d'incision

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of WO8807094A1 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19520149A1 (de) * 1995-06-01 1996-12-05 Bergmann Hans Wilhelm Endkonturnahes Laserstrahlbeschichten mit Kokille
DE19520149B4 (de) * 1995-06-01 2010-03-04 Hilti Aktiengesellschaft Vorrichtung zur Herstellung, Verfahren zur Herstellung und Verwendung einer Beschichtung auf einem Bauteil

Also Published As

Publication number Publication date
JPH01502595A (ja) 1989-09-07
EP0304488A4 (fr) 1989-09-26
WO1988007094A1 (fr) 1988-09-22
BR8707695A (pt) 1989-10-31

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