Study on structures and properties of the laser cladding exhaust valve after service

• Autorzy: Kończewicz W. , Krużycki P. , Smoleńska H.
• Języki publikacji: EN

Abstrakty

EN

The cobalt base laser cladding layers which were built up on the exhaust valve head face of the heavy loaded marine diesel engine have been investigated. The valve head with cladded face were served successfully for 3000 hours in the engine of the Dar Młodzieży. After removing from the valve head from the cylinder head the face surface were fully inspected. The surface topography and roughness were evaluated. Microstructure on the cross section of the clad layer were analyzed using Scanning Electron Microscope (SEM) equipped with energy dispersive spectroscopy (EDS. Also microhardness of the clad layer was measured. The service conditions resulted with the formation of the scale which had different thickness and tended to cracking and spalling. The microstructure of the clad layers after service did not demonstrated serious degradation process. The decrease of the hardness numbers was observed but still clad layer presented higher hardness than steel base. This type of clad layer underwent intensive laboratory examinations which contained oxidation experiments at different temperatures and corrosion in exhaust gases, long time exposition in laboratory engine and in the end 3000 hours successfully service on the ship. After such experience laser cladding cobalt base layers may be recommended as a useful solutionfor both prolongs of the service life and a method of the regeneration of the slightly used valve heads is suitable for practical applications.

Słowa kluczowe

EN

exhaust valve; laser cladding; cobalt alloy; service wear

• Wydawca: Łukasiewicz Research Network - Institute of Aviation ; European Science Society of Powertrain and Transport KONES Poland ; Wydawnictwo Instytutu Technicznego Wojsk Lotniczych
• Czasopismo: Journal of KONES
• Rocznik: 2010
• Tom: Vol. 17, No. 3
• Strony: 211--216
• Opis fizyczny: Bibliogr. 12 poz., rys.

Twórcy

autor

Kończewicz W.

autor

Krużycki P.

autor

Smoleńska H.

• Gdynia Maritime University Department of Mechanical Engineering 83 Morska Street, 81-225 Gdynia, Poland tel: + 48 58 6901564,fax: [phone],

Bibliografia

• [1] Qixian, S., Yan, S., Development of Laser Cladding Stellite F Alloy on Valve Face, Seoul 2000 FISITA World Automotive Congress, Seoul, Korea 2000.
• [2] Schlager, D., Theiler, C., Kohn, H., Protection against high temperature corrosion with laser welded claddings, applied and tested on exhaust valve discs of large diesel engines burning heavy fuel oil, Materials and Corrosion , Vol. 53, pp. 103-110, 2002.
• [3] Nando, S. K., Roskilly, A. P., Exhaust valve failure under residual fuel operation, Journal of Marine Design and Operations, No. B2, pp. 23-28, 2003.
• [4] Lijun, H., Kaushik, M. P., Liou, F. W., Modeling of laser deposition and repair process, Journal of Laser Applications, Vol. 17, Iss. 2, pp. 89-99, 2005.
• [5] Hidouci, A., Pelletier, J. M., Ducoin, F., Dezert, D., El Guerjouma, R., Microstructural and mechanical characteristics of laser coatings, Surface and Coatings Technology, Vol. 123, pp. 17-23, 2000.
• [6] De Mol Van Otterloo, J. L., De Hosson, J. T. M., Microstructural features and mechanical properties of cobalt-based laser coating; Acta Materalia, Vol. 45, No. 3, 1997.
• [7] d’Oliveira, A. S. C., da Silva, P. S. C. P., Vilar, R. M. C., Microstructural features of consecutive layers of Stellite 6 deposited by laser cladding, Surface and Coatings Technology, Vol. 153, 2002.
• [8] Smolenska, H., Effect of Temperature and Gaseous Medium on the Structure and Microhardness of the Cobalt Base Clad Layers, Chemicke Listy, Vol. 104, Iss. 15, pp. 371-374, 2010.
• [9] Li, B., Gleeson, B., Effects of Silicon on the Oxidation Behavior of Ni-Base Chromia-Forming Alloys, Oxidation of Metals Volume: 65, Issue: 1-2, February 2006, pp. 101 - 122
• [10] Smoleńska, H., The gas corrosion of the cobalt base layer at elevated temperature, Journal of Achievements in Materials and Manufacturing Engineering, Vol. 18, Iss. 1-2, pp. 235-238, 2006.
• [11] Smoleńska, H., Kończewicz, W., Analiza własności napawanych laserowo powierzchni przylgni zaworów wylotowych silników okrętowych po korozji w powietrzu i gazach spalinowych, Inżynieria Materiałowa, R. 27, Nr 3/151, s. 536-539, 2006.
• [12] Kończewicz, W., Smoleńska, H., The resistance investigation of the marine engine exchaust valve using the modelling chamber, Journal of KONES Powertrain and Transport, Vol. 15, No. 4, pp. 255-262, 2008.