INFLUENCE OF AN NANOSTRUCTURAL ELECTROPLATED COMPOSITE COATINGS ON THE TRIBOLOGICAL PROPERTIES OF THE STEEL SURFACE

This paper present a result of tribological investigations of the nanostructural electroplated composite coatings deposited on the steel surface. This layers consist the following componets: Ni-B, Ni-SiC and Ni-PTFE. The content of particles in coatings was examined gravimetrically. The roughness of the coatings Ni-SiC was measured using tester TR 100. Siemens D500 X-ray diffractometer with CuK , radiation was used to determine the dimension of nickel [111] crystallites and microstress. The microhardness of the deposited layers was measured using a Vickers’ method at a load of 0.01 and 0.05 kg. Roughness of the composite coatings was small, and it was connected with content of dispersion particles in coating and the dimension of nickel [111] crystallites. Also type of built-in particles influences on roughness of composite coatings. Microhardness increased considerably with decreasing grain size. The improved microhardness of nanocrystalline composite coatings may be due to their finer nanostructure. The tested layers fulfil a Hall – Petch relationship and their the microhardness was a function of d-1/2. Such examinated layers were subjected to the tribological tests which were carried out with the use of Amsler machine. The results of this experiments, i.e. wear resistance and coefficient of friction, show very positve effect of application nanostructural electroplated coatings for steel surface treatment. This study has shown that the wear resistance is proportional to the microhardness, the roughness, the size of nickel grain and the particle contents in composite coatings. Strengthening the nanocrystalline nickel matrix with ceramic and polymer particles gave a positive effect in the form of high wear resistance.

• Senatorski J.
• Szeptycka B.

• Технические науки. Промышленность
• Физико-математические науки
• Социальные (общественные) науки
• Естественные науки