Mechanical Properties and Corrosion-Electrochemical Behavior of Multilayer Coatings of the Ni-P and W-C System Obtained by the Electroless Plating Method and Chemical Vapor Deposition. Part 1. Structure and Mechanical Properties of Coatings

摘要

The work is devoted to the study of the properties and selection of the optimal method for applying an intermediate coating on steel, which serves as an adhesive support layer for extremely hard CVD coatings. In this work, a study of the structure and properties of multilayer coatings of the Ni-P and W-C systems was carried out. The morphology, phase and elemental composition of the layers obtained have been studied by scanning electron microscopy, X-ray diffractometry and X-ray photoelectron spectroscopy. It is shown that nickel coatings consist mainly of a metallic phase, despite the high phosphorus content in the Ni-P layers. Mechanical tests of the coatings showed that the support layer obtained by the method of electroless plating tends to increase in hardness, and tests for adhesion strength showed some advantage of electroless nickel plating over electroplating, providing a higher resistance to destructive effects during testing.