Tribological Characterization of TiAlC Nanostructured Coatings Deposited by DC Pulse Magnetron Sputtering

Abstract

In order to reveal the effect of carbon content on tribological performance of coatings, TiAlC films having four different amounts of carbon content were synthesized using DC pulse magnetron sputtering. The amount of carbon was varied by using different graphite target powers of 400, 450, 500 and 550W while keeping the TiAl target power fixed at 80W. Sliding friction and wear behavior of TiAlC nanostructured films deposited on Si (100) substrates by (DC) pulse magnetron sputtering was examined against steel ball using a ball on disk configuration' at a load of 1 N and sliding speed of 7 mm/s. The film deposited at 500W graphite target power attained a hardness of ~20.24 GPa and elastic modulus of 246 GPa. Tribological test results indicate that the film fabricated at (500W, 25 at. %C) has the lowest coefficient of friction (COF) of 0.29 and wear rate of 6.52×10−13 (mm3/Nm). The observed behavior has been attributed to presence of higher nano crystalline graphite phase, compact coating, uniform microstructure and formation of carbon rich oxide layer. Scrutiny of the nano indentation statistics showed that resistance to plastic deformation (H3/E*2) and elastic strain to failure (H/E*) increase with increasing target power and reaches the highest value at (500W, 25 at. %C) in TiAlC films.

Evaluation of adhesion strength and tribological characteristics of Ni-Co-BN nano-coating developed by magnetron sputtering

“…The tribological properties of solid lubricating coatings such as dichalcogenides of transition metals (sulphides, tellurides of tungsten, and niobium etc) is primarily used to overcome friction where liquid lubricating oils are not feasible or are ineffective. unable to prevent metal contact [11][12][13][14][15][16]. These solid lubricants, like boron nitride (BN), are made up of layers of various materials called lamellae which refer to a plate-like structure that occurs in multiples in a variety of contexts, such as bio and material sciences.…”