Frictional and Wear Behavior of Micro-Crystalline and Nano-Crystalline Diamond Films

Abstract

In the present investigation, both micro-crystalline and nanocrystalline diamond (MCD and NCD) films are fabricated, which are characterized by FESEM (Field Emission Scanning Electron Microscopy), surface profilemeter, Raman spectroscopy and Rockwell hardness tester. Moreover, under the dry environment, the frictional behavior of both the films sliding against commonly-used materials in the metal drawing industry is studied on a ball-on-plate rotational frictional tester, including the stainless steel, low-carbon steel, high-carbon steel and copper, demonstrating that the frictional coefficients between NCD films and all these materials are relatively smaller. Furthermore, the wear rates of both the films, which are hardly measured in the ball-on-plate friction tests, are evaluated using a home-made inner-hole line drawing apparatus, with both the diamond films deposited on the inner-hole surfaces and the low-carbon steel wires as the counterparts. Inversely, the NCD films present higher wear rates than the MCD ones, which can be attributed to the deteriorative film purity and adhesion.

Tribological Performance of Diamond Films with Different Roughnesses of Silicon Nitride Substrates and Carbon Source Concentrations

“…It can be seen that the variation trend of the friction coefficient of all samples was the same, which was characterized by a relatively strong and narrow peak at the beginning, mainly due to the relatively low hardness of the Si 3 N 4 ceramic ball surface during the friction sliding process. There was a plowing action of sharp diamond grain peaks, and, after a period of friction, the subsurface formed a transfer film on the diamond crystals [ 27 , 28 ]. After the running-in period, the stable wear stage was entered, and the friction coefficient also became stable.…”

Wear behaviour of gradient-multilayer diamond coatings deposited on cemented-carbide substrates

“…Chemical vapour deposition (CVD) diamond coatings have the properties of diamond, which can significantly improve the life of tools, reduce pollution during cutting, and contribute to the ecological aspects of machining [9][10][11]. CVD diamond coatings may be applied to the whole top area of the base material since they are not restricted by the intricacy of the forms to be coated [12,13]. Among the variety of CVD technologies, Hot Filament Chemical Vapour Deposition (HFCVD) has become one of the main methods because of its benefits, like structure simplification, operational simplicity, and low cost, as well as the utility of coating large areas [14].…”