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Needles are used in the textile industry for weaving. In high volume textile production a problem is wear of the needle eyelet as the threat is pulled through. This wear results in a cost to the textile manufacturer both in needle replacement, but in many cases more importantly, lost production during needle substitution The objective of this study was to examine the potential of wear resistant coatings deposited using the magnetron sputtering technique to increase the life-time of textile needles. Four coatings were evaluated, titanium nitride, titanium carbonitride, titanium diamond-like carbon and a novel coating titanium nitride/molybdenum disulphide. These coatings were selected as they have already demonstrated enhanced performance in non-lubricated tooling applications such as for drills and reamers. Initial deposition studies were carried out on flat steel substrates to facilitate the evaluation of the coatings. The deposition parameters varied were magnetron power, deposition pressure, and substrate bias during pretreatment and deposition. In order to reduce the number of experiments needed to determine the role of these various parameters on film quality the Taguchi experimental design technique was employed. The deposited coatings were evaluated using the knoop hardness, Rockwell indentation, scratch adhesion, scanning electron microscopy and a pin-on-disk wear tester. The latter technique measuring both film wear resistance and friction. In order to replicate the movement of threat through the needle eyelet during textile production a test rig was designed and built. The rig consisted of a threat being drawn through the eye of the needle at high tension to cause wear. The damage to the needle eyelet was then evaluated by semi-quantitatively measuring the wear after a certain time period. It was found that there was a considerable reduction in eyelet wear in the case of the coated needle.
Donnelly, Neil (Thesis), "Application of PVD coatings to enhance the wear life of needles used in the textile industry" (1999). Masters. Paper 42.