RU2562576C1 - Method of forming of wearproof coating of part - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: method includes build-up on the treated surface by the laser beam of the powder material in the shielding gas with creation of wearproof material layer. At that build-up is performed by the laser head with external and internal nozzles using out-of-focus laser bean. The powder and shielding gas are supplied via the gap between the nozzles coaxially with the laser beam. Then in the received wearproof layer by the same laser head and focused laser beam blind grooves are made with depth exceeding half of thickness of the build-up wearproof layer, they are filled with grease. At that the grooves can be made with depth 0.5…1.2 mm, width 0.2…0.5 mm, and spacing 1.0…3.0 mm.

EFFECT: during part working with wear the grease from the grooves enters on the work surface creating film on the contact surface, preventing intensive wear, protecting against corrosion, the grooves provide the part with grease during the entire service life.

2 cl, 4 dwg

Description

Technical field

The invention relates to a method for producing a wear-resistant coating on parts and may find application in the restoration of worn-out and hardening of new parts in various engineering industries.

State of the art

A known method of electric arc surfacing on the surface of a part of wear-resistant material (RU 2468901 C2, V23K 9/04, publ. 10.12.2012). However, the coating obtained by electric arc welding does not allow to obtain its high strength properties due to the possible formation of pores and cracks due to mixing of the deposited material with the base metal, and the electric arc surfacing has limitations on the combination of the compositions of the base and deposited materials.

A known method of laser surfacing of wear-resistant coatings, in which surfacing is performed with a laser head of a powder material using protective gas (US 4814575 A, B23K 26/00, 03/21/1989). However, the supply of lubricants to the area of rubbing surfaces is often difficult.

Disclosure of invention

The technical result of the invention is the proposed method for obtaining a wear-resistant coating with the supply of lubricant to the working surface.

A method of obtaining a wear-resistant coating on a part involves surfacing a powder material with a laser beam in a protective gas medium onto a surface to be treated to produce a layer of wear-resistant material. In this case, surfacing is performed by a laser head with external and internal nozzles by a defocused laser beam. Powder and shielding gas are fed through the gap between the nozzles coaxially to the laser beam. Then, in the obtained wear-resistant layer with the same laser head, a focused laser beam performs non-through grooves with a depth exceeding half the thickness of the deposited wear-resistant layer, which are filled with solid lubricant.

Moreover, the grooves can perform a depth of 0.5 ... 1.2 mm, a width of 0.2 ... 0.5 mm and a pitch between grooves of 1.0 ... 3.0 mm.

As a result, during operation of the part for wear, solid lubricant from the grooves falls onto the working surface, forming a film on the contact surface, preventing intensive wear, protecting against corrosion. Grooves provide the component with lubricant throughout its entire life.

List of figures

In FIG. 1 shows a deposition scheme of a wear-resistant layer by powder laser deposition, FIG. 2 - receiving grooves in the deposited layer, in FIG. 3 - filling the grooves with solid lubricant, in FIG. 4 - hit of lubricant on the working surface during operation.

The implementation of the invention

A wear-resistant layer (4) is applied to the treated surface (5) by gas laser powder surfacing. The height of the layer varies from 0.8 to 1.5 mm. Powder (6) is fed through the gap between the external (7) and internal (8) nozzles of the coaxially defocused laser beam (3). The laser beam (3) melts the metal powder (6) supplied to the surface (Fig. 1). Next, the deposited surface is treated with the same laser head with a focused laser beam (3), but without powder. With a given step (1 ... 3 mm), longitudinal grooves (2) are made onto the deposited layer by evaporation of the material (4) (Fig. 2). For this, the focus of the laser beam (3) is deepened relative to the deposited surface. The depth of the grooves is from 0.5 to 1.2 mm, the width is from 0.2 to 0.5 mm. The grooves are filled with lubricant (1) by rubbing (Fig. 3), which enters the work surface during operation (Fig. 4).

Such coatings can increase the service life of products that work on wear. The coating is fed with lubricant from the grooves throughout the entire service life; there is no need to carry out lubrication work and use additional lubricating devices.

Example

A coating was performed on parts of steel 20. A coating of 316L stainless steel was applied. Covering height - 1 mm. Then, grooves were obtained with a depth of 0.7 mm, a width of 0.3 mm, with a pitch between grooves of 1.5 mm, which were filled with graphite. As a result, the part with the obtained coating during the tests showed high indicators of wear resistance.

Claims (2)

1. A method of obtaining a wear-resistant coating on a part, including surfacing a powder material with a laser beam on a surface to be treated in a shielding gas medium to produce a layer of wear-resistant material, characterized in that the welding is performed by a laser head with external and internal nozzles with a defocused laser beam, powder and protective gas fed through the gap between the nozzles coaxially to the laser beam, then in the resulting wear-resistant layer with the same laser head, the focused laser beam performs through-hole Navki with a depth exceeding half the thickness of the deposited wear-resistant layer, which is filled with solid lubricant. 2. The method according to p. 1, characterized in that the grooves perform a depth of 0.5 ... 1.2 mm, a width of 0.2 ... 0.5 mm and a pitch between grooves of 1.0 ... 3.0 mm.

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