Wear Behaviors of Carbon-Chromium Carbide-Chromium Multilayer Coatings Prepared by Reactive High-Power Impulse Magnetron Sputtering.

Chin-Chiuan Kuo

doi:10.3390/ma14247694

Abstract

Carbon–chromium carbide–chromium multilayer coatings were deposited by utilizing reactive high-power impulse magnetron sputtering with alternating various ratios of ethyne and argon mixtures under a constant total deposition pressure, target pulse frequency, pulse duty cycle, average chromium target power, and total deposition time. Two different alternating gas mixture periods were applied to obtain films with different numbers of layers and lamination thicknesses. The results show that the reduction in the modulation period effectively affects the elastic modulus and the subsequent ratio of hardness to elastic modulus (H/E) of the whole coating, which helps adapt the elastic strain in the coating. This improves the adhesion strength and wear resistance of coatings at room temperature. However, with the increase in wear test temperature, the difference between the wear behaviors of two types of coatings becomes inconspicuous. Both types of coatings lose the wear resistance due to the decomposition of hydrocarbon and the oxidation of the chromium content in the films.

Highlights

The amorphous carbon phases exhibit a low coefficient of friction and a higher ratio of hardness to elastic modulus, which usually provides a superior wear resistance [6,17,22]
Carbon–chromium carbide–chromium tri-phase multilayer coatings with a difference modulation period were deposited by utilizing reactive high-power impulse magnetron sputtering, sequentially alternating the mixture ratios of ethyne and argon gas within the same constant deposition total pressure
Decreasing the modulation period can effectively adjust the elastic modulus and the subsequent ratio of hardness to elastic modulus (H/E) of the whole coating, which helps adapt the elastic strain in the coating

Summary

Introduction

By controlling the process parameters, various combinations of carbon and chromium, including chromium-based alloys, chromium carbides of different stoichiometric compositions, carbon-based materials and multiphase composites can be synthesized by utilizing plasma-enhanced physical vapor deposition techniques [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20]. The chromium carbides show high hardness and chemical stability at high temperature [22]. Based on these characteristics, chromium carbide coatings have been commonly used as wear and corrosion-resistant protective coatings [3,6,17,22]. Chromium carbide coatings have been commonly used as wear and corrosion-resistant protective coatings [3,6,17,22] Due to their wide adjustable range of mechanical properties, they can be used as the adhesion enhancement interlayer between metallic substrate and carbon-based topcoat [18,22]

Methods

Results

Conclusion