Investigation on the Performance Improvement of the Scroll Compressor by DLC Film

Abstract

The material property of orbiting scroll surface, mainly affects the life and performance of scroll compressors. Generally, the anodic oxide film (AOF) is used in the surface treatment of the domestic orbiting scroll, which has numerous drawbacks such as poor adhesion of the film-substrate and easy wear failure. In this paper, a process producing the diamond-like carbon film (DLCF) on the surface of an orbiting scroll by unbalanced magnetron sputtering technology was proposed based on the mechanical characteristics of the scroll compressor and the surface treatment method of the orbiting scroll. The friction coefficient, microhardness, film-substrate adhesion and other performances of the AOF and DLCF were analyzed from the data measured by various test facilities. The refrigeration capacity, power and volumetric efficiency of compressors with different coatings were analyzed and compared by tests under different operating conditions with fixed values of refrigerant charge and oil content. The surface morphology of the coatings was then studied by scanning electron microscope to identify the microstructure after the operation. The results showed that a more even and dense surface was obtained by the DLCF compared with the AOF, which improved the wear resistance of the surface. The surface friction coefficient was only 0.11 as the Cr transition layer markedly enhanced the bonding strength. The DLCF displayed more properties of graphite with the thickness of only 0.73 μ m. The volumetric efficiency of the compressor under the nominal operating condition increased by 5.8%.

Key Technologies and Application of Electric Scroll Compressors: A Review

“…Park et al [10] applied the Darveaux method, considering the Bauschinger effect in ductile materials, to assess the fatigue life of aluminum alloy scroll compressors. Ji et al [11,12] developed a technique for depositing diamond-like carbon films (DLCFs) onto scroll surfaces using unbalanced magnetron sputtering technology, while considering mechanical properties and surface treatment methods. Compared to anodized oxide film (AOF), DLCF provides a more uniform and compact surface, enhancing wear resistance.…”

The Tribological Behavior of Cast Iron by Laser Surface Texturing under Oil-Lubricated Initial Line Contact for Rotary Compressor

“…For refrigeration compressors, considerable efforts have been made to reduce the friction loss and elevate the wear resistance. Therein, the protective surface coating [13,14] and structural optimization [15] are the current main means. For example, for the protective surface coating, He et al [16] experimentally verified the feasibility of diamond-like carbon film (DLC) for scroll compressors and showed the DLC had a low friction coefficient and a high bonding strength due to its excellent wear-reducing and self-lubricating property.…”