Friction Durability and Nanowear of Extremely thin Diamond-Like Carbon Films Dependence on Film Thickness| Chapter 5 | Science and Technology: Developments and Applications Vol. 6

Nanotribology is a key technology for the advanced mechanical industry. The development of advanced micro- and nano-mechanical systems, bio-technology elements, automobile mechanics and so on have been realized in recent years. Nanotribology is a key technology for the advanced mechanical industry. The development of advanced micro- and nano-mechanical systems, bio-technology elements, automobile mechanics and so on have been realized in recent years. Tribological durability properties of extremely thin diamond-like carbon (DLC) films (target thickness 0.03–5 nm) deposited using filtered cathodic vacuum arc (FCVA) and plasma-chemical vapor deposition (P-CVD) methods were evaluated using load-increase-and-decrease, ball-on-disk, and low-load reciprocating friction tests. Friction durability notably increased at a certain film thickness for FCVA-DLC and P-CVD-DLC films. These thicknesses were nearly equal to surface roughness and corresponded to film thickness at which the nanowear profiles changed from protuberance to grooves and at which nanoscratch resistance increased. Excellent friction durability of FCVA-DLC films (thickness ≥ 0.4 nm), evaluated by the rapid increase in the friction coefficient, was observed. In contrast, the friction durability of P-CVD-DLC films gradually increased when the film thickness was 0.6 nm or greater. When the thickness of the DLC films was 2.0 nm or greater, the films did not exhibit a rapid increase in their friction coefficient within the total number of testing cycles. The tribological properties of extremely thin DLC films depend on film thickness; extremely thin FCVA-DLC films exhibit excellent wear resistance. The film thickness at which FCVA-DLC films endured the total number of test cycles was approximately one-fifth the corresponding thickness of P-CVD-DLC films, evaluated by the three different friction tests. The friction durability notably increases at a certain film thickness. FCVA-DLC films (thickness ≥ 0.4 nm) exhibited excellent friction durability. The ratio between the durable film thickness of FCVA-DLC and P-CVD-DLC films was about 1/5. Friction durability dependence on thickness corresponds to the nanowear properties.

 

Author (s) Details

 

Shojiro Miyake
MS Laboratory, 3-1, Gonokami, Hamra-City, Tokyo 205-0011, Japan and Nippon Institute of Technology, 4-1, Miyashito-Machi, Minamisaitama, Saitama, 345-8501, Japan.

 

Masatoshi Miyake
MS Laboratory, 3-1, Gonokami, Hamra-City, Tokyo 205-0011, Japan and Nishogakusya University, 6-16, Sanbancho, Chiyoda-Ku, Tokyo 102-8336, Japan.

 

Please see the book here:- https://doi.org/10.9734/bpi/stda/v6/4450

Regression Analysis of Nano and Macrotribological Properties of Diamond-Like Carbon Films Deposited Through a Filtered Cathodic Vacuum Arc Ion-Plating Method | Chapter 3 | Advances and Challenges in Science and Technology Vol. 6

 Diamond-like element (DLC) films have been extensively used in industries on account of their excellent characteristics in the way that high severity. In particular, there is a growing demand for their use as guarding films for mechanical parts on account of their excellent wear resistance and reduced friction cooperative. DLC films have been deposited by miscellaneous methods and many be dissimilar the DLC regions present in the ternary drawings proposed for sp3 covalent element, sp2 covalent carbon, and hydrogen.  Bend filtered photoelectric vacuum curve (FCVA) approach with dc and pulsed bias heat is used to produce diamond-like element (DLC) films. Atomic force microscopy was used to assess how changeful the bias voltage damaged the characteristics of nanoindentation and nanowear. The hardest DLC films had an average hardness of 50 GPa, a depressed dissipation modulus, a depressed elastic modulus to nanoindentation hardness percentage, and a strong nanowear opposition when they were deposited with a dc bias strength of 50 V. Nanoindentation hardness was definitely correlated with the Raman peak percentage Id/Ig, whereas wear wisdom was negatively correlated at this moment ratio. These nanotribological features highly depend on the films’ nanostructures. The tribological possessions of the FCVA-DLC films were also examined using a ball-on-disc test. The average friction cooperative of DLC films deposited with dc bias heat was lower than that of DLC films located with pulse bias service. The friction cooperative calculated from the ball-on-plate test was correlated accompanying the nanoindentation hardness in dry conditions. However, under horizon lubrication environments, the friction coefficient and particular wear rate had little correlation accompanying nanoindentation hardness, and wear behavior appeared to be affected by other factors to a degree adhesion substance between the film and substrate.

Author(s) Details:

Shojiro Miyake,
MS Laboratory, 3-1, Gonokami, Hamura-City, Tokyo 205-0011, Japan.

Masatoshi Miyake,
MS Laboratory, 3-1, Gonokami, Hamura-City, Tokyo 205-0011, Japan.

Please see the link here: https://stm.bookpi.org/ACST-V6/article/view/12130

Improvement of Friction Durability of Magnetic Head-Disk Interfaces by Thin Lubricant Films on Diamond-like-carbon Protective Layers | Chapter 4 | Current Topics and Emerging Issues in Materials Sciences Vol. 1

 Nanowear and viscoelasticity were judged to study the nanotribological properties of lubricant films of Z-tetraol, D-4OH, and A20H on gemstone-like-carbon guarding layers, including their memory and replenishment properties. For A20H and dense Z-tetraol-coated disks, the plate surface partially protrudes, and the point lag (tan δ ) increases accompanying friction. Good replenishment authorizes the lubricant to reflow and cover areas exhausted after flowing contact between the head and disk. The memory and replenishment of lubricants depend on their interplays with the gemstone-like carbon (DLC) film on the surface of the disc. This result is consistent with renewal of the lubricant upon tip falling. For the D-4OH-coated disk, the tan δ advantage decreases with tip sliding, identical to the case for the unlubricated disk. The grit of the lubricant-coated drawing disks was then determined using friction tests accompanying increasing and decreasing loads. Regardless of the load, the unlubricated plate's friction force fast increases after about 30 reciprocating eras. By plotting the friction cooperative's relationship accompanying the load and reciprocating cycle number, the lubricating state can be calculated. There are four types in which the disagreement coefficient can be established. In addition, the changes in the friction coefficient were plan with respect to the lubricating state, emphasizing four distinct extents of lubricant management. The lowest friction area forms fluid lubrication. The second area forms the transition to assorted lubrication. The third district constitutes boundary lubricating. The highest resistance of the fourth area results from surface rupture. The boundary lubricating area of the A20H lubricator was wide, by way of its good retention and renewal properties.

Author(s) Details:

Shojiro Miyake,
MS laboratory, 3-1, Gonokami, Hamura-city, Tokyo 205-0011, Japan.

Shota Suzuki,
Sanshinseiki, 3-15-18 Yaguchi, Ota Ward, Tokyo 146-0093, Japan.

Masatoshi Miyake,
MS laboratory, 3-1, Gonokami, Hamura-city, Tokyo 205-0011, Japan.

Please see the link here: https://stm.bookpi.org/CTEIMS-V1/article/view/10311