PLASMA SPRAYING METHOD FOR COATING A CYLINDER BARREL OF A CYLINDER CRANKCASE OF A RECIPROCATING INTERNAL COMBUSTION ENGINE

Abstract

A plasma spraying method for coating a cylinder barrel of a cylinder crankcase of a reciprocating internal combustion engine. A coating method is provided, with the aid of which the formation of oxides is limited or oxide banding in the layer formation and thus negative influences are avoided due to oxidation outbreaks and microgroove formation are avoided. The coating is applied to the cylinder barrel of the cylinder crankcase at least partially using the following parameter combination: rotational speed: 600 to 800 revolutions/minute; sprayed material delivery rate: 80 to 180 grams/minute; and feed rate: 24 to 75 mm/s.

Claims

1. A plasma spraying method comprising: coating a cylinder barrel of a cylinder crankcase of a reciprocating internal combustion engine; and applying the coating, at least partially, to the cylinder barrel of the cylinder crankcase using the following parameter combination: rotational speed: 600 to 800 revolutions/minute; sprayed material delivery rate: 80 to 180 grams/minute; and feed rate: 24 to 75 mm/s.

2. The plasma spraying method according to claim 1, wherein the coating is applied with the aid of 5 to 8 spray cycles, in the form of double strokes in each case.

3. The plasma spraying method according to claim 1, wherein a steel layer or a ceramic layer is applied as the coating.

4. The plasma spraying method according to claim 1, wherein the coating is applied with the aid of a low-alloy steel powder.

5. The plasma spraying method according to claim 1, wherein a steel layer is applied as the coating with the aid of a steel powder having a predominantly spherical morphology with small proportions of satellites.

6. The plasma spraying method according to claim 1, wherein a steel layer is applied as the coating with the aid of a steel powder, which has less than 2 wt % carbon (C), less than 2 wt % manganese (Mn), less than 2 wt % chromium (Cr), less than 1 wt % nickel (Ni), less than 1 wt % oxygen (O.sub.2) and less than 1 wt % nitrogen (N.sub.2).

7. The plasma spraying method according to claim 1, wherein a steel layer is applied with the aid of a steel powder whose grain size is smaller than 60 m or is smaller than 42 m.

8. The plasma spraying method according to claim 1, wherein the coating is applied under the influence of the atmosphere (APS method).

9. The plasma spraying method according to claim 1, wherein the coating is applied using a protective gas or in a vacuum.

10. The plasma spraying method according to claim 1, wherein at least one blasting abrasion process is carried out before the coating is applied, using corundum and/or water, via laser beam abrasion or by abrasion with the aid of a geometrically defined cutting edge.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein:

[0024] FIG. 1 shows a cross-sectional representation of a detail of a cylinder barrel having a coating;

[0025] FIG. 2 shows a view of a surface of a coating of a cylinder barrel according to the prior art;

[0026] FIG. 3 shows a cross section of a coating on a cylinder barrel manufactured using a method according to the invention; and

[0027] FIG. 4 shows an enlarged representation of the detail according to FIG. 3.

DETAILED DESCRIPTION

[0028] FIG. 1 shows a detail of a cylinder crankcase of a reciprocating internal combustion engine, including a detail of a cylinder barrel of an aluminum base body 10 of a cylinder crankcase 14, aluminum base body 10 being provided with a coating 12, and surface 16 facing away from aluminum base body 10 being part of cylinder barrel 18 of cylinder crankcase 14. Areas 20 partially marked in black are oxides, which have formed during the application of coating 12 with the aid of a plasma spraying method.

[0029] FIG. 2 shows surface 16 of cylinder barrel 18. As is apparent in the figure, individual oxide bands 22a, 22b, 22c, 22d have formed on surface 16, which are formed by black dots, which are arranged approximately in a row. This is the oxide banding mentioned at the outset.

[0030] FIG. 3 shows a view similar to FIG. 1, coating 12 having been applied with the aid of a plasma spraying method according to the invention.

[0031] FIG. 4 shows an enlarged representation of the view from FIG. 3. As is apparent, surface 16, which forms cylinder barrel 18 of cylinder crankcase 14, has a much higher quality, in that the oxide banding is no longer apparent. Moreover, it is apparent that much less oxide has formed in coating 12 than in coating 12 according to the prior art, which is illustrated in FIG. 1.

[0032] The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims: