To access the full text documents, please follow this link:

Surface modification of HVOF thermal sprayed WC-CoCr coatings by laser treatment
Chikarakara, E.; Aqida, S.; Brabazon, D.; Naher, S.; Picas Barrachina, Josep Anton; Punset Fusté, Miquel; Forn Alonso, Antonio
Universitat Politècnica de Catalunya. Departament de Ciència dels Materials i Enginyeria Metal·lúrgica; Universitat Politècnica de Catalunya. CDAL - Centre de Disseny d´Aliatges Lleugers i Tractaments de Superfície
In this work the affects of laser characteristics on microstructure and microhardness of high velocity oxygen fuel sprayed (HVOF) WC–CoCr coatings were investigated. The coating was deposited with a Sulzer Metco WokaJet™-400 kerosene fuel and the laser surface treatments were applied using CO2 laser with 10.6 μm wavelength. Large variations in surface properties were produced from variation in the laser processing parameters. In total, four levels of peak power (100, 200, 300 and 350 W), four levels of spot diameter (0.2, 0.4, 0.6 and 1 mm) and three levels of pulse repetition frequency (PRF) were investigated. An initial set of tests were followed by a more detailed 33 factorial design of experiments. Pulse repetition frequency and duty cycle were set in order to maintain the same overlap in the x and y directions for the raster scanned sample spot impact dimensions. Overlaps of 30% were used in the initial tests and 10% in the more detailed trials. The results have shown that care must be taken to keep the irradiance at a relatively low level compared to uncoated surfaces. High irradiance can in this case result in rough and porous surfaces. Lower levels of irradiance are shown to provide more uniform microstructures, reduced porosity and increased microhardness.
Peer Reviewed
Àrees temàtiques de la UPC::Enginyeria electrònica::Optoelectrònica::Làser
Àrees temàtiques de la UPC::Física::Física de l'estat sòlid::Superfícies
Surface preparation
Thermal spraying
Laser surface hardening
Superfícies -- Tractament

Show full item record

Related documents

Other documents of the same author

Chikarakaraa, Evans; Punset Fusté, Miquel; Picas Barrachina, Josep Anton; Brabazon, Dermot; Naher, S.
Picas Barrachina, Josep Anton; Punset Fusté, Miquel; Baile Puig, Maria Teresa; Martín Fuentes, Enrique; Forn Alonso, Antonio
Picas Barrachina, Josep Anton; Baile Puig, Maria Teresa; Menargues Muñoz, Sergi; Martín Fuentes, Enrique; Forn Alonso, Antonio
Menargues Muñoz, Sergi; Campillo Betbese, Manel; Baile Puig, Maria Teresa; Picas Barrachina, Josep Anton; Forn Alonso, Antonio
Menargues Muñoz, Sergi; Baile Puig, Maria Teresa; Campillo Betbese, Manel; Picas Barrachina, Josep Anton; Forn Alonso, Antonio