Laser Treatment of Plasma Spraying Alloyed Coatings

Jasim Kadhim, Mohammed; Ibrahim Jaffar, Sami; Adnan Anon, Eman

doi:10.30684/etj.30.16.15

	Laser Treatment of Plasma Spraying Alloyed Coatings
Engineering and Technology Journal
Article 1, Volume 30, Issue 16, 2012, Pages 343-354 PDF (818.77 K)
DOI: 10.30684/etj.30.16.15
Authors
Mohammed Jasim Kadhim; Sami Ibrahim Jaffar; Eman Adnan Anon
Abstract
Ni23Cr6Al0.4Y plasma sprayed coating on nimonic75 substrate was remelted using a 1 kW continues CO2 laser. The topography, microstructure, phases and chemical analysis of plasma sprayed and laser melted regions were examined using various techniques including scanning electron microscope (SEM), electron probe microanalysis (EPMA), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). The plasma sprayed coatings consisted heterogeneous microstructure of lamella with unmelted particles, voids, porosity and cracks. It was found that the depth of melting increased with increasing the specific energy. Homogenous and shiny melted regions were achieved without voids, porosity and cracks after laser melting. Thin upper surface layers with shallow cracks were observed due to the rich layer of α-Al2O3 and YAlO3. No phases changed were found before and after laser melting of plasma sprayed layers. The phases formed are mixtures of γ’, β, YAlO3 in the matrix γ. The microstructure formed after laser melting is fine cells. Keywords: Plasma sprayed coating; Laser melting, Ni solid solution; YAlO3; α-Al2O3
Keywords
Plasma sprayed coating; Laser melting; Ni solid solution; YAlO

Statistics Article View: 295 PDF Download: 157