Functional Coatings, Deposited Using Flexible Electrode Tapes
Keywords
Abstract
The paper considers the possibility of obtaining wear-resistant coatings of considerable thickness on the surfaces of parts made of iron alloys by arc welding in the environment of protective gases. In this case, a common low-carbon welding wire is used, and the hardness, wear resistance and other properties of the coating are ensured by the use of a flexible electrode tape applied to the surface, being strengthened. The offered tape consists of fabric of organic origin, on which the required mixture of doping powders with a special glue is applied. During the arc burning, a welding bath is formed between the welding wire and the workpiece. In this bath, the carbon of the organic fabric of the tape and the complex of the mixture of applied doping powders are dissolved, with the subsequent formation of hard wear-resistant compounds in the coating. This makes it possible to form coatings of high hardness without using an additional operation — heat treatment on low-carbon steels. An additional positive effect is the possibility of grinding the structure of the surface layer, surfacing of the curved surfaces and holes with hardness and wear resistance in accordance with local loads. A comparative analysis of surfacing results was performed without and with the use of a flexible electrode tape. The rollers and the shape of the formed coating do not differ significantly in different surfacing methods. The structure of the used flexible electrode tape is shown and described. It was established that the proposed surfacing technology allows to increase the hardness of the surface, to obtain a fine-grained structure, and to change the local hardness of the coating according to the requirements. The solubility in the welding bath of carbon contained in the fabric of natural origin and applied doping powders has been experimentally proven. It was determined that the creation of the coatings with various properties depends on the thickness of the used fabric and the applied doping complex.
