Analyzing Properties of New Hard Coating Technologies for Increasing the Wear Resistance

Abstract

The aim of this paper is, improving the characteristic of Ventilation mill for grinding coal which is one of the main part of steam power plants in the system that makes a significant influence on the level of energy efficiency with its work. Working parts of the mil during exploitation are dominantly exposed to intensive abrasive and erosive wear and also to impact loading at elevated temperatures, which can lead to damage and fracture of homogeneous materials, thus shortening their working life. For solving the problem of increasing the wear resistance of the parts for transport and coal grinding in power plants, to investigate the optimum application of technology in hard coatings by different procedures, and filer materials. Hard coatings were carried out with cold (plasma and arc treatment) and hot metallization (with concurrent and subsequent drowning). It has been used the additional materials of different chemical composition and properties based on Ni (NiCrBSi; NiCrBSiFe; NiCrBSi / WC) and Fe (FeCrCSiMo; FeCrCBSiTi; FeCrCBNiSi). The main goal of this paper is to make the selection of optimum hardfacing procedures, group of filler materials and hardfacing technology definition based on the results of structural and mechanical properties of samples, experimental model hardfacing. These were investigation of its structure, measurement and distribution of hardness in the samples, tribology characteristic samples with hard coatings. Based on the results of these tests there were selected the additional materials and procedures for applying hard coatings, which would be apply in the revitalization of parts in transport at and coal grinding.