Proceedings of SerbiaTrib '13

Serbian TribologySocietySERBIATRIB ‘1313 th International Conference onTribologyKragujevac, Serbia, 15 – 17 May 2013Faculty of Engineeringin KragujevacTRIBOLOGICAL BEHAVIOR OF THERMAL SPRAY COATINGS,DEPOSITED BY HVOF AND APS TECHNIQUES, ANDCOMPOSITE ELECTRODEPOSITS NI/SIC AT BOTH ROOMTEMPERATURE AND 300°C.A.Lanzutti 1 , M. Lekka 1 , E. Marin 1 , L.Fedrizzi 11 Università di Udine, Dipartimento di Scienze e Tecnologie Chimiche, Via del Cotonificio 108, 33100 Udine Italy,alex.lanzutti@uniud.itAbstract: Both the thermal spray and the electroplating coatings are widely used because of their high wearresistance combined with good corrosion resistance. In particular the addition of both micro particles ornano-particles to the electrodeposited coatings could lead to an increase of the mechanical properties,caused by the change of the coating microsctructure.The thermal spray coatings were deposited following industrial standards procedures, while the Ni/SiCcomposite coatings were produced at laboratory scale using both micro- and nano-sized ceramic particles.All the produced coatings were characterized regarding their microstructure, mechanical properties and thewear resistance. The tribological properties were analyzed using a tribometer under ball on diskconfiguration at both room temperature and 300 o C.The results showed that the cermet thermal spray coatings have a high wear resistance, while the Ni nanocompositeshowed good anti wear properties compared to the harder ceramic/cermet coatings deposited bythermal spray technique.Keywords: thermal spray coatings, nano-composite electrodeposits, Ni/SiC, micro-compositeelectrodeposits, HVOF, APS, dry sliding, 300°C).1. INTRODUCTIONThe thermal spray coatings are widely used formany industrial applications [1-13] because of thepossibility to deposit different type of materials,ranging from different metal alloys to ceramics, andtheir technological properties, in particular the highwear resistance even if they are used also ascorrosion barriers at both high temperaturedegradation or wet corrosion.The thermal spray coatings are mainly used forhigh temperature applications (oxidation resistanceor fused salts resistance). Usually these types ofcoatings are deposited with the addition of rareearths in order to inhibit the oxidative degradationprocesses [1-3]. Some technological processes areused to reduce the porosity of the coating and thusincrease both mechanical properties and the barriereffect to oxidative environments. Sidhu et al [2]have found that the laser remelting process increaseboth the mechanical properties and the oxidationresistance and leaves only a small amount ofporosity to the coating (