Hard tribological

FIG. 20-75 Fluid-bed erosion or wear rate as a function of granule material properties. Kq is fracture toughness and H is hardness as measured hy three-point bend tests. [Ennis [Pg.1888]

TFL is an important sub-discipline of nano tribology. TFL in an ultra-thin clearance exists extensively in micro/nano components, integrated circuit (IC), micro-electromechanical system (MEMS), computer hard disks, etc. The impressive developments of these techniques present a challenge to develop a theory of TFL with an ordered structure at nano scale. In TFL modeling, two factors to be addressed are the microstructure of the fluids and the surface effects due to the very small clearance between two solid walls in relative motion [40]. 

Tribology performances and applications of ordered molecular films have been a long-standing research subject in SKLT, the workplace for the authors of this book. Hu and Luo [42] prepared SAMs of fluoroalkylsilane (FAS) and poly-fluorealkylmethacrylate (PFAM) on the magnetic head of computer hard disk drivers. Experiment results show that the molecular films greatly improve the performance of the... 

The research work on carbon nitride materials was first motivated due to its hypothetical super-hardness. The tribological properties of the CNx films are, of course, the emphasis of the succeeding research works. Although the expected structure and hardness have not been achieved up to the present, the potential interesting properties still stimulate many approaches on the tribological behavior of CNx films. Figure 8 gives the results of hardness measurement reported by the... 

Bhushan, B., Chemical, Mechanical and Tribological Characterization of Ultra-Thin and Hard Amorphous Carbon Coatings as thin as 3.5 nm Recent Developments," Diamond Relat. Mater., Vol. 8,1999,pp. 1985-2015. 

Yang, M. C., Study on Nano-Tribology at Head/Disk Interface of Computer Hard Disk Drives," Ph.D. Thesis, Tsinghua University, Beijing, China, 2001. 

The tribochemical reactions based on the hard and soft acids and bases (HSAB) principle linked to the friction coefficient (p) are summarized above. The effect of tribological processes consists of the formation of mixed short-chain phosphate glasses containing sulfide precipitates. 

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