Studies of adhesive and wear-resistant properties of chrome coatings for car parts and road construction equipment restoration

Abstract

Introduction. The use of chrome plating as a method of restoring parts that work with waterjet wear is important for restoring the operability of hydraulic drive units and parts used in specialized vehicles and road construction equipment. The proposed method of chrome recovery has the necessary advantages, it is a sufficiently high performance and microhardness of the resulting chrome coatings. However, for implementation in production, additional studies of the reliability of the chrome coatings obtained, namely, adhesion strength and wear resistance, were required. This will make possible to draw conclusions about the prospects for further implementation and use for the restoration of hydraulic drive parts and other parts that work with waterjet wear.Materials and methods. To conduct the research, equipment meeting the requirements of technical conditions, using existing and developed devices and devices for obtaining chrome precipitation was used. For this purpose, the necessary devices and samples from the appropriate material to approximate the reliability of the obtained research results were made. Also the necessary improvements to digitize the data obtained on the friction machine were made.Results. The performed studies of adhesion strength have shown that the chrome coatings obtained from the new electrolyte composition will make possible to obtain adhesion strength reaching 270 MPa, which is sufficient for parts operating at high pressures (20 MPa) with the necessary margin of safety. Also the studies conducted on the wear resistance of chrome coatings let to conclude that the wear resistance of the chrome coatings obtained is 20-30% higher compared to the reference surface (the material of the spool manufacture).Discussion and conclusion. The studies of the obtained chrome coatings from the new electrolyte composition made possible to establish, which let to establish the regularities of the influence of the electrolyte composition and the modes of testing the wear resistance of the precipitation obtained compared with the existing universal chromium plating electrolyte. The results obtained confirmed the possibility of using a chrome coating from a new chromium plating electrolyte for the restoration of car parts and road construction machines operating under waterjet wear.