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
  • C23C4/04—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 method for producing a sprayed surface with a defined roughness on a workpiece and the use of the method or the surface produced thereby.
• thermally sprayed layers After spraying, thermally sprayed layers have a rough surface, the degree of roughness of which lies within a relatively large fluctuation range.
• the roughness results from the splintering of molten particles when they hit the workpiece surface to be coated. This sputtering can be stronger or weaker depending on the temperature of the particle, which means that very different roughness can occur on a single surface. If such surfaces are used in areas where, on the one hand, a special grip of the surface is required and, on the other hand, this grip must not damage the product, the use of the layers described at the outset is not possible due to the roughness fluctuations mentioned. In addition, depending on the alloy used, the service life of such surfaces is too short for many applications. A remedy was achieved here with moderate success by grinding the sprayed surfaces in a second operation and thus achieving a defined roughness within certain limits.
• the inventor has set himself the goal of improving the method of the type mentioned at the outset and including a surface layer to offer clearly defined roughness in relatively easy handling.
• the solution to this problem is that a powdery material made of a mixture of a matrix based on Ni, Co and / or Fe-based alloy and hard materials and a grain size distribution of these hard materials with a maximum proportion between 25 to 150 microns, the sprayed - but unsintered layer has a surface roughness in the range Ra 10 to 100 ⁇ m with a defined roughness of Ra.x ⁇ 20 ⁇ m and x is a number from 10 to 100 ⁇ m.
• the sprayed-on layer has a defined surface roughness of Ra.x ⁇ 10 ⁇ m.
• the hard materials have a melting point of about 1200 ° C and higher.
• the coating of surfaces with a defined roughness of x ⁇ 20 ⁇ m, preferably ⁇ 10 ⁇ m - where x is the desired surface roughness in ⁇ m - in the range from 10 to 100 ⁇ m leads to long service lives if a mixed powder is used as the powdery material uses, which consists of two or more components that have a larger melting interval and hard materials. Powdery materials based on an alloy of Ni, Co and / or iron are best suited for such a matrix. According to the invention, the melting point interval of these alloys should be between 900 and 1400 ° C., preferably between 1000 and 1300 ° C., and should have an interval of more than 50 ° C.
• Hard material particles such as carbides, borides, nitrides, silicides and oxides are used as carriers for the roughness.
• the mixing ratio of the two components matrix / hard material should be between 20 and 80% by weight, preferably 30 to 60% by weight, for the hard material portion.
• the surface roughness is influenced via the grain distribution of the hard material portion, i. H. the maximum proportion of the grain distribution is kept very narrow, while the total distribution is in the ranges from 37 to 125 ⁇ m or 45 to 105 ⁇ m or 45 to 90 ⁇ m or 37 to 75 ⁇ m.
• the hard material particles should be produced by spray drying, agglomerating with and without sintering or by melting with subsequent breaking and grinding. Later coating of the hard materials with Ni, Co and / or Fe has proven to be advantageous.
• the proportion should be below 40% by weight, preferably below 20% by weight.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Plasma & Fusion (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Materials Engineering (AREA)
• Mechanical Engineering (AREA)
• Metallurgy (AREA)
• Organic Chemistry (AREA)
• Coating By Spraying Or Casting (AREA)

Applications Claiming Priority (2)

Publications (2)

Family

ID=6325622

Family Applications (1)

Country Status (7)

Cited By (7)

Families Citing this family (4)

Family Cites Families (5)

• 1987
  • 1987-04-14 DE DE19873712684 patent/DE3712684A1/de active Granted
• 1988
  • 1988-03-29 FI FI881474A patent/FI86748B/fi not_active Application Discontinuation
  • 1988-04-12 EP EP88105778A patent/EP0287023A3/fr not_active Withdrawn
  • 1988-04-13 IN IN303/CAL/88A patent/IN169734B/en unknown
  • 1988-04-13 CA CA000563978A patent/CA1315613C/fr not_active Expired - Fee Related
  • 1988-04-14 BR BR8801864A patent/BR8801864A/pt not_active IP Right Cessation
  • 1988-04-14 CN CN198888102725A patent/CN88102725A/zh active Pending

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