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
  • C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
• • 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

• Iron-containing layer of a sliding surface applied by thermal spraying in particular for cylinder running surfaces of engine blocks
• the invention relates to an iron-containing layer of a sliding surface applied by thermal spraying, in particular for cylinder running surfaces of engine blocks, according to the preamble of claim 1 and to a method for producing and using this layer.
• WO 03/106718 a generic iron-containing layer is known, which is applied by thermal spraying and which has an amorphous structure with finely divided, nano-crystalline metal bonds and / or metal carbides.
• a layer is well suited as a sliding surface due to its high hardness.
• the layer in the area of the sliding surfaces is applied to the machine parts to be coated by thermal spraying.
• the resulting surface of the sprayed-on layer is relatively rough and, in order to serve as a sliding surface, must be smoothed by surface treatment.
• Such machining is preferably carried out by honing, but other machining and non-machining methods of surface machining are also possible.
• the sprayed-on layer must be partially removed. In order for this to be possible, compromises between strength and machinability must be found in the formation of the sprayed-on layer, above all with regard to the total manufacturing effort and the associated manufacturing costs. As a result, the sliding surface formed does not always have the best possible properties with regard to wear resistance and / or sliding friction, especially in connection with a lubricant, which it could have due to the superior properties of the iron-containing layer.
• the iron-containing layer thus has further nano-crystalline metal borides and / or metal carbides which have arisen after the application of the iron-containing layer and a subsequent surface treatment by selective heat input into the iron-containing layer.
• Another advantage is that the surface treatment is carried out after the iron-containing layer has been applied.
• the surface of the iron-containing layer can thus be finished as far as possible after the application, so that the final surface roughness and / or the final layer thickness is achieved.
• the layer is applied in such a way that a favorable surface treatment, e.g. B. in terms of accuracy and / or costs.
• the subsequent heat input causes a change in the properties of the layer, e.g. B. greater hardness, better wear behavior and / or better sliding friction behavior in the area of heat input.
• the post-processing of the surface that may be necessary to z. B.
• removing burrs or achieving a lower surface roughness can then be limited to a minimum.
• heat e.g. B. with laser light
• no roughening the Surface noticeable. All in all, this enables high-precision production of a sliding surface with the best possible wear and friction behavior at low production costs.
• the surface treatment can be a mechanical finishing of the iron-containing layer. These are e.g. B. honing, grinding or polishing. These tried and tested methods allow the surface of a sliding layer to be produced inexpensively and precisely. So that the sliding surface can be essentially finished, that is, a subsequent processing after the heat input is no longer necessary or is limited to a small amount of post-processing to z. B. to remove burrs caused by heat input.
• finely divided nanocrystalline metal borides and / or metal carbides are advantageously eliminated from the amorphous structure of the iron-containing layer.
• the iron-containing layer can thus have a relatively high proportion of crystalline and / or partially crystalline structure when applied. This allows the cheap mechanical processing.
• the heat input creates additional nanocrystalline metal borides and / or metal carbides, which significantly increases the strength of the iron-containing layer in the area of the heat input.
• the iron-containing layer preferably has a hardness of 1000 to 1250 HV 0.05 in the area of the heat input, but the hardness can easily be set in the range between 800 HV 0.05 and 1500 HV 0.05 by appropriate process parameters and material composition.
• Such hardness is currently z. B. in hard metal tools based on tungsten carbide / cobalt, and can now also be used for sliding surfaces over a large area. Due to the high hardness, the iron-containing layer is extremely wear-resistant.
• the metal borides or metal carbides preferably have a size of 60 to 130 nm. Due to the small size, the friction is reduced and the hardness increased.
• the selective heat input advantageously has the shape of geometric figures, regular patterns and / or irregular patterns.
• FIGS. 1-10 can be made by continuously introducing heat, in that a selective heat source is guided over the iron-containing layer in accordance with the shape of the figures and patterns.
• the heat input can also be carried out discontinuously, for. B. to create a dot pattern.
• adjacent areas can be created on the sliding surfaces, each of which has different properties.
• the iron-containing layer has ablutions that have arisen from the selective heat input. This can e.g. B. done by removing material on the surface of the layer by evaporation. The removals can again be in the form of figures or patterns, as previously described. Such abrasion on sliding surfaces in the form of lubrication pockets, oil collecting grooves, or the like can improve the sliding friction properties.
• Finely distributed nanocrystalline metal borides and / or metal carbides are preferably precipitated from the amorphous matrix of the iron-containing layer at the edge of the removal. So that the wear resistance of the edge, for. B. a lubrication pocket, significantly increased and it is ensured that the function of the lubrication pocket, etc. is reliably performed even after a long period of operation.
• the removal preferably takes the form of local depressions.
• Such depressions are known from EP1275864.
• the disclosure content of this document is incorporated into the disclosure of this application by reference.
• the depressions have a maximum extension of less than 2 mm. It has proven to be advantageous dimensions for lubrication pockets if the depressions have a maximum length of 2 mm, a maximum width of 70 ⁇ m and a maximum depth of 40 ⁇ m. This represents a good compromise between the tribological properties and the manufacturing costs of the lubrication pockets. Because of these dimensions, individually or in combination, the optimal function of the recesses as lubrication pockets of the sliding surface is guaranteed. These dimensions are not to be understood as restrictive. These dimensions can also be larger or smaller for certain applications. In particular, there is no particular dimensional ratio of the depressions to be observed. Rather, each of the dimensions length, width and depth can be adapted to the requirements of the respective recess.
• the heat is preferably introduced by means of laser light and / or electron beams.
• These energy sources can selectively selectively introduce heat or energy into the iron-containing layer in a small area, as z. B. is required to produce the wells described above.
• these energy sources in a confined space, such as. B. within a cylinder race of an internal combustion engine or a hydraulic cylinder can be used to produce the inventive iron-containing layer.
• inventive iron-containing layer can be produced in any suitable combination with the method for producing an iron-containing layer, and conversely the inventive method can also be used for producing an iron-containing layer.
• the inventive iron-containing layer is used in the production of sliding surfaces on machine parts, in particular connecting rod bearings, crankshaft bearings, piston rings, cylinder running surfaces and pistons.
• machine parts in particular connecting rod bearings, crankshaft bearings, piston rings, cylinder running surfaces and pistons.
• this includes all machines where such machine components are located, e.g. B. hydraulic cylinders, gears, shaft bearings.
• Preferred applications are highly loaded cylinder running surfaces of supercharged diesel and petrol engines. Due to the high mechanical bracing of the Layer with the base material, the coating is particularly suitable for thermal shock-stressed motors. Thermal shock occurs when, during a cold start at low ambient temperatures, the engine revs quickly to maximum speed under load. Since the iron-containing layer has an amorphous structure with finely divided, nano-crystalline metal bonds and / or metal carbides, the sliding surface is highly resilient, since a layer with extremely high hardness is created due to the nano-crystalline precipitates of the metal borides and metal carbides. Furthermore, the borides lead to a very low coefficient of friction, so that this layer also has excellent sliding properties.
• a preferred use of the iron-containing layer according to the invention can be used in the repair of worn sliding surfaces.
• the layer has an excellent mechanical connection or clinging to the base material due to the amorphous solidification and is therefore able to be applied subsequently.
• the layer can be applied to a reworked, cleaned and / or blasted surface. This allows the layer to be used flexibly for any repair work on sliding surfaces. Due to the high hardness and strength of the layer, any weakening of the base material due to wear or subsequent removal is compensated for, so that the original strength of the base material can almost be restored.
• Application example is the critical land area between cylinder bores of an engine block.
• FIG. 1 shows a schematic section through an iron-containing layer
• Fig. 2 is a microscope image of an iron-containing layer in the area of heat input.
• Figure 1 shows a base material 1, on which an iron-containing layer 2 is applied.
• Layer 2 is already finely machined on surface 3 and has reached its final surface finish as a sliding surface.
• a laser beam 4 is used to introduce heat into the layer 2 with a high energy density, thereby creating a region 5 of the heat input which is approximately limited by the boundary line 6.
• the material of layer 2 partially evaporates and the recess 7 is formed, which preferably extends in the form of a lubrication pocket over layer 2.
• a width b of up to 70 ⁇ m and a depth t of up to 40 ⁇ m have proven to be advantageous dimensions.
• the longitudinal extent is not shown here, but a maximum length of not more than 2 mm has proven advantageous here.
• FIG. 2 shows a microscope image of an iron-containing layer in the area of the heat input.
• Such a material structure results, for example, in an area which is marked with the detail 8 in FIG. 1.
• the iron-containing layer 2 applied has an area 5 of the heat input. This was created in that the recess 7 was produced by material evaporation due to heat input by means of a laser beam, not shown.
• the area 5 shows, especially in the edge zone 9 of the recess 7, an increased density of finely divided nano-crystalline metal bonds 10 and metal carbides 10 compared to the base material of the layer 2, where no heat treatment was carried out.
• the edge zone 9 in the region 5 of the heat treatment thus has an even greater hardness than the non-heat-treated layer 2 itself.

Priority Applications (3)

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Publications (1)

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ID=34638796

Family Applications (1)

Country Status (4)

Cited By (5)

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Citations (9)

Family Cites Families (16)

• 2005
  • 2005-01-28 EP EP05100575A patent/EP1559806A1/de not_active Withdrawn
  • 2005-01-28 DE DE502005009857T patent/DE502005009857D1/de active Active
  • 2005-01-28 AT AT05707873T patent/ATE473311T1/de not_active IP Right Cessation
  • 2005-01-28 EP EP05100596A patent/EP1559808A1/de not_active Withdrawn
  • 2005-01-28 EP EP05100597A patent/EP1559807A1/de not_active Withdrawn
  • 2005-01-28 EP EP05707873A patent/EP1711642B1/de active Active
  • 2005-01-28 WO PCT/EP2005/050357 patent/WO2005073425A1/de not_active Application Discontinuation

Patent Citations (9)

Non-Patent Citations (1)

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