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2629865 
Journal Article 
Characterization of Welding Fume from SMAW Electrodes - Part II 
Sowards, JW; Ramirez, AJ; Dickinson, DW; Lippold, JC 
2010 
1 
Welding Journal
ISSN: 0043-2296 
89 
4 
82S-90S 
WOS:000276289900015 
In Part I of this study, an electrical low pressure impactor (ELPI) was used to collect welding fume from E6010, E7018, and E308-16 electrodes and determine number and mass distributions based on fume particle diameter. Fume generation rates were obtained using an improved fume hood design, and bulk fume phases were identified using X-ray diffraction (XRD). Part II of this study makes use of extensive characterization work by evaluating fume particles (collected in different size ranges with the ELPI) with scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Transmission electron microscopy (TEM) was used to characterize fume particles in the ultrafine (< 0.3 mu m) range. Using these techniques, fume particles were classified into three distinct morphologies: spherical, irregular, and agglomerate. Agglomerates were the most common particle type observed followed by spherical and irregular. Many of the spherical and agglomerated particles exhibited a core-shell structure where a core, rich in metal oxides, was coated with a shell consisting of more volatile elements (Si, Na, Mg). This core-shell morphology was evident in fumes generated by all three of the shielded metal arc welding (SMAW) electrodes. Extensive chemical analysis was conducted on a large number of particles and agglomerates over the entire size range (0.03-10 mu m) collected in the ELPI. Fume composition was found to vary as a function of aerodynamic diameter, which was attributed to the different fume formation mechanisms. 
Electrical Low Pressure Impactor (ELPI); X-Ray Diffraction (XRD); Scanning Electron Microscopy (SEM); Shielded Metal Arc Welding (SMAW); Welding Fume