Tribological properties of multilayer tetrahedral amorphous carbon coatings deposited by filtered cathodic vacuum arc deposition

AbstractTetrahedral amorphous carbon (ta-C) has emerged as an excellent coating material for improving the reliability of application components under high normal loads. Herein, we present the results of our investigations regarding the mechanical and tribological properties of a 2-µm-thick multilayer ta-C coating on high-speed steel substrates. Multilayers composed of alternating soft and hard layers are fabricated using filtered a cathodic vacuum arc with alternating substrate bias voltages (0 and 100 V or 0 and 150 V). The thickness ratio is discovered to be 1:3 for the sp2-rich and sp3-rich layers. The results show that the hardness and elastic modulus of the multilayer ta-C coatings increase with the sp3 content of the hard layer. The hardness reached approximately 37 GPa, whereas an improved toughness and a higher adhesion strength (> 29 N) are obtained. The friction performance (µ = 0.07) of the multilayer coating is similar to that of the single layer ta-C thick coating, but the wear rate (0.13 × 10−6 mm3/(N·m)) improved under a high load of 30 N. We further demonstrate the importance of the multilayer structure in suppressing crack propagation and increasing the resistance to plastic deformation (H3/E2) ratio.

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Structure and Tribological Properties of Ultra-Thin Tetrahedral Amorphous Carbon (ta-C) Films

Tribology ◽

10.1115/imece2006-14412 ◽

2006 ◽

Author(s):

Xinchun Lu ◽

Hui Wang ◽

Chenhui Zhang ◽

Jianbin Luo

Keyword(s):

Amorphous Carbon ◽

Tribological Properties ◽

Electron Spectroscopy ◽

Vacuum Arc ◽

Wear Properties ◽

Force Microscopy ◽

Tetrahedral Amorphous Carbon ◽

Atomic Force ◽

Transmission Electron ◽

Filtered Cathodic Vacuum Arc

Ultra-thin tetrahedral amorphous carbon (ta-C) films were deposited by the filtered cathodic vacuum arc (FCVA) technique. The thickness, structure, and topography of the films were studied by various analysis methods, such as auger electron spectroscopy (AES) depth profile, high resolution transmission electron microscope (HRTEM), Raman spectroscopy, and atomic force microscopy (AFM). A tribometer was used to investigate the tribological properties of the ta-C films. The results indicate that ta-C film with thickness less than 2 nm can be obtained by the FCVA technique. As the film thickness increases the relative intensity ratio ID/IG decreases, which means that sp3 bond in the films increases. The oxide layer cleaning procedure of silicon substrate before deposition influences the growth mode and surface roughness of the films. The ultra-thin ta-C film has the lowest friction coefficient of 0.19 and excellent anti-wear properties.

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Influence of hydrogen on the structure and properties of tetrahedral amorphous carbon films obtained by the filtered cathodic vacuum arc technique

Philosophical Magazine B ◽

10.1080/014186399256466 ◽

1999 ◽

Vol 79 (10) ◽

pp. 1647-1658

Author(s):

L. K. Cheah, X. Shi, E. Liu, B. K. Tay

Keyword(s):

Amorphous Carbon ◽

Carbon Films ◽

Vacuum Arc ◽

Structure And Properties ◽

Amorphous Carbon Films ◽

Tetrahedral Amorphous Carbon ◽

Filtered Cathodic Vacuum Arc

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FCVA-Synthesized Tetrahedral Amorphous Carbon Films for Biomedical Applications

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.336-338.1577 ◽

2007 ◽

Vol 336-338 ◽

pp. 1577-1580 ◽

Cited By ~ 2

Author(s):

Chuan Lin Zheng ◽

Wu Bao Yang ◽

X. Chang

Keyword(s):

Amorphous Carbon ◽

Biomedical Applications ◽

Pure Titanium ◽

Carbon Films ◽

Vacuum Arc ◽

Negative Bias Voltage ◽

Tetrahedral Amorphous Carbon ◽

In Vitro Measurements ◽

Filtered Cathodic Vacuum Arc

Tetrahedral amorphous carbon (ta-C) films were deposited onto Si(100) wafers by using filtered cathodic vacuum arc technique (FCVA). The influence of the negative bias voltage applied to substrates on film structures was studied by Raman spectroscopy, X-ray photoemission spectroscopy (XPS). The ta-C films showed maximal sp3 fractions 87%, the hardness and elastic modulus of the ta-C film is 72 and 480 GPa, respectively. In vitro measurements of contact angle and platelet adhesion were applied to evaluate the biocompatibility of the ta-C films in comparison with that of NiTi, 316L and pure titanium. The results show that the ta-C films have hydrophobicity and exhibit better hemocompatibility which are very suitable for biomedical applications.

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