CN211370565U

CN211370565U - Cylinder liner with high layer adhesion strength aluminum-based outer coating

Info

Publication number: CN211370565U
Application number: CN201922034066.3U
Authority: CN
Inventors: 米歇尔·布赫曼; 彼得·戈德尔; 克里斯蒂安·斯沃齐尔
Original assignee: Federal Mogul Friedberg GmbH
Current assignee: Federal Mogul Friedberg GmbH
Priority date: 2019-11-14
Filing date: 2019-11-21
Publication date: 2020-08-28
Anticipated expiration: 2029-11-21
Also published as: DE202019106342U1

Abstract

The utility model relates to a cylinder liner (2) of outer coating based on aluminium with high-rise adhesion strength, this cylinder liner have on the surface of the housing based on aluminium coating (8), this coating has covered the surface of the housing of cylinder liner (2) at least partially. Wherein the coating (8) has a layer adhesion strength of between 40MPa and 55 MPa.

Description

Cylinder liner with high layer adhesion strength aluminum-based outer coating

Technical Field

The utility model relates to a cylinder liner, this cylinder liner have apply to the coating based on aluminium on the casing surface and have higher layer adhesion strength on cylinder liner.

Background

In principle, it is known to use coated cylinder liners, wherein first an inner coating is known which serves as a wear protection layer. It is also known to use an adhesion promoting layer in a cylinder liner that is cast into an engine block to achieve a metallic connection with the material of the engine block. This is particularly desirable in the case of iron-based cylinder liners that are to be cast into aluminum engine blocks to achieve a good connection between the iron material of the cylinder liner and the aluminum material of the engine block.

SUMMERY OF THE UTILITY MODEL

In particular in cast cylinder liners, it is desirable to improve the bond between the material of the cylinder liner and the material of the engine block. It is therefore also desirable to provide a cylinder liner having an outer coating that is particularly firmly connected to the material of the liner, and which also allows a particularly firm connection with the material of the engine block when cast.

This is achieved by the cylinder liner having a coating on the outer surface of the shell. The coating is an aluminum-based coating. The coating is mounted on and at least partially covers an outer surface of a housing of the cylinder liner. The coating has a layer adhesion strength of between 40MPa and 90MPa, preferably between 45MPa and 70MPa, and more preferably between 45MPa and 55 MPa. It can also be provided that the coating has a layer adhesion strength of at least 45MPa and an average of 55 MPa.

The layer adhesion strength was determined by tensile testing. In this test method, three circular disks having a diameter of 20mm are cut out from the cylinder liner in the radial direction (in the axial direction at the upper/middle/lower portion). The two sides of the disk/manifold (outer diameter with Al coating and inner diameter of iron) were bonded with a draw bolt. The adhesive materials used, for example, Delo Monopopox AD295, HKT Ultrabond 100, have an adhesive strength of at least 100 MPa. The tensile specimen was clamped in a gimbal table (to avoid lateral forces on the contact faces) and tested in a tensile tester. The samples were subjected to a test speed of 250N/s. For example, if the layer is completely removed from the substrate with a normal force of 20000N, there is a layer adhesion strength of 64 MPa. The layer adhesion strength was determined as the average of three sample measurements per cylinder liner. The deviation of the layer adhesion strength of the bent sample from the flat sample (where the layer adhesion strength of the bent sample is lower than that of the flat sample due to the shear force) is taken into account by a correction factor.

The cylinder liner has an aluminum-based coating in order to achieve a particularly good connection to the engine block cast from aluminum or an aluminum alloy during casting. The coating is mounted on an outer surface of a casing of the cylinder liner, and the coating at least partially covers the coating to cover portions of the cast cylinder liner. It is also possible to provide only a part of the later cast face with a coating, for example to positively influence crack propagation, wherein the load of the cylinder liner is so great that the locations between the cylinder liner and the engine block where cracks are expected to occur are not coated. The coating has a layer adhesion strength of between 40MPa and 90MPa, preferably between 42MPa and 70MPa, and more preferably between 45MPa and 55MPa, so as to be able to absorb forces occurring between the engine block and the cylinder liner during engine operation without detachment occurring between the layer and the base material of the cylinder liner. By means of the aluminum material of the coating, it is achieved that the coating at least partially melts during the casting process and is thus welded to the aluminum casting material.

According to an exemplary embodiment, the cylinder liner may also be provided with a wear protection layer on the inner side.

In another exemplary embodiment of the cylinder liner, the coating is an electric arc wire spray coating. In this case, a well-adhering coating can be achieved, in particular by using a small atomizer gas pressure or amount in combination with a high process voltage and a low wire feed. In particular, a significantly higher layer adhesion strength compared to other methods can be achieved by a high particle temperature at which the particles strike the surface.

Here and additionally and in the claims, the percentage data are to be understood in the sense of weight percentages (wt%).

In another exemplary embodiment of the cylinder liner, the aluminum-based coating comprises, and is preferably made of, an aluminum-silicon alloy. The coating should here comprise at least one aluminum-based alloy or aluminum-silicon alloy, wherein further alloy constituents may also be present. In a preferred embodiment, the further alloy components are aluminum-silicon alloys which may contain only individual impurities, which are respectively below 2% and below 4% in total, preferably respectively below 1% and below 4% in total, more preferably respectively below 0.5% and below 2% in total. The aluminum alloy on the one hand allows for a protruding adhesion on the coated surface and, in addition, allows for a protruding melting or welding with the cast material of the engine block in which the cylinder liner sleeve is cast.

In additional exemplary embodiments of the cylinder liner, the coating includes a composition having Al, AlSi, Al₂O₃And/or SiO₂Preferably between 1% and 3% of other residual materials. Here, the residual material may include inevitable or inevitable impurities made of the wire spray material, a remainder composed of a processing agent such as a cooling lubricant, a cutting oil, a processing oil, or an anticorrosive. These processing agents and impurities may also be further chemically altered by the arc during the spraying process.

In another exemplary embodiment of the cylinder liner, the aluminum-based coating consists of the aluminum-silicon alloys AlSi10 to AlSi14, preferably AlSi11 to AlSi13, more preferably AlSi12, wherein between 0.5% to 4%, preferably 1% to 3%, more preferably 1.5% to 2.5% of other residual materials are allowed or included. Such alloys achieve, on the one hand, outstanding layer adhesion strength on the material of the cylinder liner in the case of thermally sprayed layers and, on the other hand, good connection or castability with the engine block material. It is thereby ensured that the cylinder liner does not come loose between the iron-based material and the coating or between the coating and the cast material, even during operation of the engine.

In another exemplary embodiment of the cylinder liner, the aluminum-based coating is an aluminum-silicon alloy, the aluminum-silicon alloy comprisingAl, Al content₂O₃And Si and residual materials. The aluminum content is between 75% and 95%, Al₂O₃The content is between 0.5% and 4%, the Si content is between 1% and 15%, and the remainder is formed by residual material between 1% and 23.5%.

Here, preferably, the aluminum content may be 80% and 90%, Al₂O₃Between 1% and 3% and a Si content between 5% and 13%, wherein the residual material is preferably present between 1.5% and 2.5%.

The aluminum content is between 75% and 95%, preferably between 80% and 90%, more preferably between 83% and 87%, and Al₂O₃Between 0.5% and 4%, preferably between 1% and 3%, and further preferably between 1.5% and 2.5%, with a Si content between 1% and 15%, preferably between 5% and 13%, more preferably between 10% and 12%, with the remainder being formed by residual material, wherein preferably the residual material is between 1% and 23.5%, more preferably between 1.5% and 2.5%. In the examples given here, the compositions are respectively chosen such that the individual components add up to 100%.

In another exemplary embodiment of the cylinder liner, the layer thickness of the coating is between 100 μm and 400 μm, preferably between 140 μm and 300 μm, and more preferably between 180 μm and 240 μm. The values given here allow a sufficiently large coverage of the surrounding surface and suitable melting properties during casting, so that a layer adhesion strength between the cast material and the aluminum-based coating of between 40MPa and 90MPa, preferably between 42MPa and 80MPa, and more preferably between 45MPa and 55MPa, can also be achieved.

In another exemplary embodiment of the cylinder liner, the cylinder liner has a wall thickness of 1mm to 3mm, preferably 1.2mm to 2.5mm, and more preferably 1.5mm to 2 mm. The wall thickness is related to the thickness of the circumferential surface of the cylinder liner, without regard to the molded flange or groove. The wall thickness preferably relates to the wall thickness of the cylinder liner, including the coating. The wall thickness is to be understood here as a wall thickness whose area represents at least 80%, preferably 90%, of the area of the cylinder liner. As long as the cylinder liner is only partially coated, only the wall thickness of the coated portion should be taken into account here.

In another exemplary embodiment of the cylinder liner, the base material of the cylinder liner is an iron-based alloy, such as steel or gray cast iron.

Gray cast iron alloys for the gasket material generally consist of 2-4% by weight carbon, 1-3% silicon, up to 1% manganese, 0.2-1% chromium and up to 0.5% copper, the remainder being iron. The cast steel consists of 0.5% carbon, 1% manganese, 0.5% silicon, the remainder being iron. In addition, other alloying elements, such as nickel or chromium, may be added.

In an additional exemplary embodiment of the cylinder liner, the aluminum-based coating is a thermal arc sprayed coating. Electric arc spraying is particularly suitable here, since atomization of the particles can be achieved economically by means of compressed air. The surface of the aluminum particles is oxidized, which means that an exothermic reaction occurs. That is, the particles become hotter and more tightly clamped to the roughened substrate surface. In addition, arc spraying allows for a wide range of coatings. Depending on the process voltage used, the selected wire feed of the jet gas and the type/amount of atomizing gas, the properties of the coating can be influenced.

In another exemplary embodiment of the cylinder liner, the coating has an average roughness of 60 to 150 μm, preferably 80 to 130 μm, more preferably 90 to 110 μm. More preferably, the average roughness is always lower than the layer thickness of the coating. The relatively large roughness results in a large surface, which in turn enables a rapid melting of the layer during casting. The preferred spray parameters, with which a higher layer adhesion strength can be achieved, also favor a relatively large roughness. The layer adhesion strength is achieved here by the spray parameters which achieve particularly hot particles when applied to the surface to be coated. The roughness must be below the layer thickness of the coating in order to exclude defective locations of the coating. In a continuous porous coating, the layer adhesion strength cannot be determined by the above-described method, since the test carrier then adheres not only to the coating but also to the base material of the cylinder liner in the region of the through-holes or pores. In this case, the determined layer adhesion strength can be distorted by the direct connection of the adhesive to the substrate. Thus, the coating is designed as a closed coating.

In another exemplary embodiment of the cylinder liner, the coating has a layer porosity of between 6% and 20%, preferably between 8% and 12%, and more preferably between 9% and 11%. Herein, layer porosity describes how high a proportion of pores are in a layer, but not the size or coverage of the pores. The pores are smaller than the layer thickness, so that unclosed coatings are avoided. The porosity creates a larger area that enables better heat transfer from the cast material to the coating material when cast. A better connection between the cast material and the coating may avoid separation between the coating and the cast material of the engine block during operation.

In the thermal spraying process, the coating is formed from molten and accelerated droplets which are projected in the direction of the surface. These droplets have partially solidified on the outside on the way to the surface, but the particles remain liquid on the inside. After the particles or metal droplets impinge on the outer surface of the cylinder liner, they remain there. By means of said impact, the particles form respectively more or less round and flat coating elements which can be regarded as spray surfaces, spray projections, spray cakes or spray patches and are referred to below as splashes.

According to an exemplary embodiment, the coating comprises particularly large splashes. In another exemplary embodiment of the cylinder liner, the coating has a splash diameter of between 80 and 400 μm, preferably between 100 and 300 μm, more preferably between 150 and 200 μm. In another exemplary embodiment of the cylinder liner, the coating has a splash diameter greater than 100 μm. The splash portion has a large diameter in the circumferential direction and in the axial direction, but not in the radial direction, since the coupling piece is strongly flattened in this direction. Large splashes are produced by high arc currents and high arc voltages, which are combined with a small atomizing gas pressure. The large metal droplets and the spray particles have a more favorable substance-surface ratio, whereby the spray particles are less strongly cooled and impinge hotter on the surface, and can thus be better clamped on said surface. The splash portion is larger and can therefore better adhere to the substrate and form a larger contact surface with the substrate. The particles can transfer more heat through the larger mass and form larger structures. Due to the larger particles, care must be taken that the velocity of the particles is not too high during coating to prevent a too large part of the particles from atomizing during impact.

In another exemplary embodiment of the cylinder liner, the cylinder liner has an outer diameter of 50mm to 180mm, preferably 60mm to 150mm, and more preferably 80 to 120 mm. The utility model particularly relates to a vehicle engine field especially relates to automobile engine.

In an additional exemplary embodiment of the cylinder liner, the cylinder liner is disposed on an outer surface of the at least one circumferential groove or on an outer surface of the at least one recess. In this case, the surface of the at least one circumferential groove or of the at least one depression is likewise coated. These recesses also help anchor the cylinder liner in the engine block by a form fit. Furthermore, the dimples increase the surface that is cast and, therefore, increase the strength of the connection between the cylinder liner and the engine block. It can also be provided that the entire outer surface is provided, for example, with small depressions, as is the case in golf balls or honeycomb. Thereby, besides a material fit, also form-fitting parts may contribute to the anchoring of the cylinder liner sleeve in the engine block.

According to another aspect of the present invention, there is provided an engine and/or engine block with a cast cylinder liner as described above.

Drawings

The invention is explained below with the aid of exemplary and schematic drawings, in which:

fig. 1 shows a coated cylinder liner in a partial sectional view.

Figure 2 shows the removal of three sample bodies.

Fig. 3A to 3E show steps of determining the layer adhesion strength of the cylinder liner.

Fig. 4 shows an exemplary embodiment of a coated cylinder liner with two circumferential grooves at the outer periphery.

Fig. 5 shows an exemplary embodiment of a partial coating. It is provided, for example, that the upper edge of the cylinder liner and/or the lower edge of the cylinder liner are not coated.

Detailed Description

In the following, the same reference numerals will be used in the drawings and the drawings to refer to the same or like parts or features.

Fig. 1 shows a perspective partial section through a double-layered cylinder liner 2 according to the invention. The cylinder liner 2 includes a base material formed of cast iron or steel that forms the base 4. The base body 4 is essentially an uncoated cylinder liner. The coating 8 forms together with the base body 4 a cylinder liner 2 according to the invention. The coating 8 covers the outer circumferential surface of the base body 4 at least partially. It is provided, for example, that the upper edge may not be coated. It can also be provided that the lower edge of the cylinder liner is not coated. The cylinder liner 2 may further be provided with a flange, not shown. The coating 8 comprises a material formed of an aluminium-based alloy. The coating 8 is manufactured by arc wire spraying and has a layer adhesion strength between 45MPa and 55 MPa. This is achieved by a particularly hot arc in combination with a relatively low spray pressure and thus a relatively low velocity of the sprayed particles. Other coatings achieved layer adhesion strengths of between 40MPa and 90MPa by arc wire spraying.

It can be seen from this figure that the cylinder liner forms a bimetallic tube, however, this is not relevant due to the small layer thickness of the coating 8 and the relatively soft aluminum substrate. In contrast, in cast cylinder liners, the bimetallic effect produces a very strong effect, since the material cannot be easily deformed. The forces generated by the bimetallic effect have to be absorbed at the boundary between the base body 4 and the coating 8, so a very high layer adhesion strength of at least 40MPa and preferably between 45MPa and 70MPa is particularly important. The wall thickness a of the cylinder liner is shown together with the coating thickness B. The thickness B of the coating 8 is here between 100 μm and 400 μm. In the present case 210 μm thick. It is clear that the drawings are not to scale. The total thickness a of the wall thickness is between 1 and 3mm and in the example shown is 1.8 mm.

Fig. 2 shows the removal of the test body from the cylinder liner 2 according to the invention. For this purpose, a plurality of sample bodies 40 are removed, for example, by means of a core drill or by means of laser cutting or by means of another cutting method. The uppermost sample body 40 is only cut away and only the cutting, sawing or perforation lines are visible. The central sample body 40 is slightly pushed out of the cylinder liner 2 in the radial direction. The lower sample body 40 is shown completely separated from the cylinder liner 2. The sample body preferably has a sample diameter of between 10 and 30mm in order to keep the measurement distortions due to the curvature of the contact surface between the substrate 4 and the coating 8 as small as possible.

Fig. 3A shows an enlarged view of the sample body 40 of fig. 2. The sample body 40 is shaped like a flat cylinder or disk. However, the end face of the sample body 40 is constituted by a portion of a coaxial cylindrical surface.

Fig. 3B shows a side view of the sample body 40 of fig. 3A. The sample body 40 has a diameter of 10mm and a wall thickness a of 2 mm. A slight curvature of the surface and the cylinder inner surface can be seen in the side view.

Fig. 3C shows a side view of the sample body 40 of fig. 3A, with two test carriers 44 adhered to the sample by the adhesive 42. The test carrier 44 is matched in shape to the end face of the sample body 40 in order to achieve the thinnest possible adhesive bond or the smallest possible adhesive gap. The test carrier is provided with openings in order to be able to subject the sample body to tensile loads. In the ideal case, the curvature of the end face of the sample body 40 has no influence on the determination of the layer adhesion strength and can be ignored. This can be demonstrated by further experiments using smooth sample bodies and identical material pairings.

In fig. 3D, the sample body 40 is loaded by a tensile force exerted on two test carriers 44, wherein the force with which the separation of the coating 8 from the base material of the cylinder liner occurs divided by the sample area is converted into a layer adhesion strength.

Fig. 3E shows the destroyed sample body 40 and two test carriers 44. The coating 8 is torn off from the substrate by the pulling force applied in fig. 3D. In the event that the adhesive 42 tears off relative to one of the coated substrate or test body, there is an erroneous measurement and the test must be repeated. The arithmetic mean of at least three sample volumes is determined, the arithmetic mean having to be higher than 40MPa and preferably between the desired 45MPa and 70 MPa.

The binder can be different for the respective pair, i.e. the aluminium test carrier or the cast iron/steel test carrier. It is also possible to use test carriers made of different materials for the coating 8 and the base body 4 in order to be able to absorb high tensile forces. It is noted that the measurement method can only be used for closed layers, since in the case of through-holes in the coating to the cast iron or steel, the result will be distorted by the layer adhesion strength of the binder on the cast iron or steel.

Fig. 4 shows a coated cylinder liner 2 according to the invention, the base body 4 of which is reduced in the region of the axial ends of the cylinder liner by means of the recesses 18. The cylinder liner 2 comprises two outer grooves 8, an upper outer groove and a lower outer groove, respectively. The location and width of the grooves may vary. Further inwards, also wider and flatter grooves can be considered. It is likewise provided that only round or angular depressions are provided on the base body 4. Here, the recess 18 and the depression are covered by the coating 8.

Fig. 5 shows a coated cylinder liner 2 according to the invention. The coating 8 ends before the lower end of the substrates 4, respectively. The cylinder liner shown in FIG. 5 is one example of a cylinder liner that is only partially coated. The cylinder liner shown may protrude into the crankcase on the lower end. It can also be provided that the cylinder liner projects beyond the upper contact surface with respect to the cylinder head, for example, in order to achieve a higher surface pressure of the cylinder head seal with respect to the cylinder head. The upper edge is embodied rotationally symmetrical, while the lower edge has rotational and mirror symmetry.

In addition to the tensile test, in which the cut-out circular segments are clamped between the tie rods, bonded and the coating is subsequently removed, a curved tensile die made of steel can also be glued directly to the coated cylinder liner and removed via a tensile device (PAT test). The layer adhesion strength was calculated from the extraction force and the punch cross section. It must be noted that the surface of the cylinder liner being coated does not deform when the punch is extracted.

List of reference numerals

2 Cylinder liner

4 base body made of cast iron or steel or uncoated cylinder liner

8 aluminum-based coating

18 grooves/surrounding recesses

40 sample body

42 adhesive

44 test carrier

46 breakage part

Wall thickness of cylinder liner

Layer thickness of B coating

Claims

1. A cylinder liner (2) having a coating (8) at the outer surface of the shell,

it is characterized in that the preparation method is characterized in that,

the coating (8) is an aluminium-based coating,

and is

The coating (8) has a layer adhesion strength of between 40MPa and 90MPa,

or

The coating (8) has a layer adhesion strength of at least 40MPa and an average of 55 MPa.

2. The cylinder liner (2) of claim 1, wherein the coating (8) is an electric arc wire spray coating.

3. The cylinder liner (2) according to claim 1 or 2, characterized in that the aluminum-based coating comprises an aluminum-silicon alloy.

4. Cylinder liner (2) according to claim 3, characterized in that the aluminium-based coating (8) comprises the aluminium-silicon alloys Al, AlSi, Al₂O₃And/or SiO₂。

5. The cylinder liner (2) of claim 4, wherein the aluminum-based coating (8) comprises the aluminum silicon alloy AlSi10 to AlSi14, further comprising between 0.5% and 4% residual material.

6. Cylinder liner (2) according to claim 4, characterized in that the aluminium-based coating (8) comprises an aluminium-silicon alloy Al, Al₂O₃Si and residual material, wherein the aluminum content is between 75% and 95%, Al₂O₃Is between 0.5% and 4%, wherein the Si content is between 1% and 15%, wherein the remainder is formed by residual material.

7. The cylinder liner (2) according to claim 1 or 2, characterized in that the aluminum-based coating (8) has a layer thickness between 100 and 400 μ ι η.

8. The cylinder liner (2) according to claim 1 or 2, characterized in that the cylinder liner (2) has a wall thickness of 1mm to 3 mm.

9. The cylinder liner (2) of claim 1 or 2, characterized in that the base material of the cylinder liner (2) is steel or gray cast iron.

10. The cylinder liner (2) according to claim 1, characterized in that the aluminum-based coating (8) is a thermal arc sprayed coating.

11. The cylinder liner (2) according to claim 1 or 2, characterized in that the coating (8) has an average roughness of 60 μ ι η to 150 μ ι η, wherein the average roughness is always lower than the layer thickness of the coating (8).

12. The cylinder liner (2) according to claim 1 or 2, characterized in that the coating (8) has a layer porosity of between 6% and 20%.

13. The cylinder liner (2) according to claim 1 or 2, characterized in that the coating (8) has a splash diameter between 80 μ ι η and 400 μ ι η.

14. The cylinder liner (2) according to claim 1 or 2, characterized in that the cylinder liner (2) has an outer diameter of 50mm to 180 mm.

15. The cylinder liner (2) according to claim 1 or 2, characterized in that the cylinder liner (2) has at least one circumferential groove (18) and/or at least one recess on the outer surface.

16. The cylinder liner (2) of claim 1, wherein the coating (8) has a layer adhesion strength of between 42MPa and 80 MPa.

17. The cylinder liner (2) of claim 1, wherein the coating (8) has a layer adhesion strength of between 45MPa and 55 MPa.

18. The cylinder liner (2) according to claim 3, characterized in that the coating consists of an aluminum silicon alloy.

19. The cylinder liner (2) of claim 4, wherein the coating further comprises between 1% and 3% residual material.

20. The cylinder liner (2) of claim 5, characterized in that the coating comprises the aluminum silicon alloys AlSi11 to AlSi 13.

21. The cylinder liner (2) of claim 5, wherein the coating comprises an aluminum silicon alloy AlSi 12.

22. The cylinder liner (2) of claim 5, wherein the coating comprises between 1% and 3% residual material.

23. The cylinder liner (2) of claim 5, wherein the coating comprises between 1.5% and 2.5% residual material.

24. The cylinder liner (2) of claim 6, characterized in that the aluminum content is between 80% and 90%.

25. The cylinder liner (2) of claim 6, characterized in that the aluminum content is between 83% and 87%.

26. Cylinder liner (2) according to claim 6, characterized in that Al₂O₃Is comprised between 1% and 3%.

27. Cylinder liner (2) according to claim 6, characterized in that Al₂O₃Is comprised between 1.5% and 2.5%.

28. The cylinder liner (2) according to claim 6, characterized in that the Si content is between 5% and 13%.

29. The cylinder liner (2) according to claim 6, characterized in that the Si content is between 10% and 12%.

30. The cylinder liner (2) of claim 6, characterized in that the residual material is between 1% and 23.5%.

31. The cylinder liner (2) of claim 6, characterized in that the residual material is between 1.5% and 2.5%.

32. The cylinder liner (2) according to claim 7, characterized in that the coating has a layer thickness between 140 and 300 μm.

33. The cylinder liner (2) according to claim 7, characterized in that the coating has a layer thickness between 180 and 240 μm.

34. The cylinder liner (2) according to claim 8, characterized in that the cylinder liner (2) has a wall thickness of 1.2mm to 2.5 mm.

35. The cylinder liner (2) according to claim 8, characterized in that the cylinder liner (2) has a wall thickness of 1.5mm to 2 mm.

36. The cylinder liner (2) according to claim 9, characterized in that the steel is 0.3 to 0.6% carbon, 0.8 to 1.2% manganese, 0.3 to 0.7% silicon and optionally nickel or chromium, with the remainder consisting of iron and unavoidable impurities.

37. Cylinder liner (2) according to claim 9, characterized in that the cast iron consists of 2-4% by weight of carbon, 1-3% of silicon, up to 0-1% of manganese, 0.2-1% of chromium and up to 0.5% of copper, the remainder consisting of iron and unavoidable impurities.

38. The cylinder liner (2) according to claim 11, characterized in that the coating (8) has an average roughness of 80 μ ι η to 130 μ ι η.

39. The cylinder liner (2) according to claim 11, characterized in that the coating (8) has an average roughness of 90 μ ι η to 110 μ ι η.

40. The cylinder liner (2) of claim 12, characterized in that the coating (8) has a layer porosity of between 8% and 12%.

41. The cylinder liner (2) of claim 12, characterized in that the coating (8) has a layer porosity of between 9% and 11%.

42. The cylinder liner (2) according to claim 13, characterized in that the coating (8) has a splash diameter of between 100 and 300 μ ι η.

43. The cylinder liner (2) according to claim 13, characterized in that the coating (8) has a splash diameter between 150 μ ι η and 200 μ ι η.

44. The cylinder liner (2) according to claim 13, characterized in that the coating (8) has a splash diameter of more than 100 μ ι η.

45. The cylinder liner (2) according to claim 14, characterized in that the cylinder liner (2) has an outer diameter of 60mm to 150 mm.

46. The cylinder liner (2) according to claim 14, characterized in that the cylinder liner (2) has an outer diameter of 80mm to 120 mm.