A method for qualitative photoelectronic spectroscopic determination of a content of different valence manganese in a solid component of welding fume (SCWF) was developed.
For the first time, a presence of bi- and tivalent manganese (Mn2+ and Mn3+) as well as tetravalent one (Mn4+) was found in SCWA of basic type coated electrodes.
Data about dispersion degree and morphology of SCWF formed in welding with basic and rutile types coated electrodes were obtained using laser granulometry method and scanning electron microscopy. Influence of composition of electrode coating and dispersion degree of coating materials on intensity and specific weight of SCWF emissions was investigated. It was shown that an increase of content of active deoxidizers in the coating composition results in reduction of SCWF emissions.
(Prof. I. K. Pokhodnay, I. R. Yavdoshchin, S. N. Stepanyuk, I.P. Gubenya)Manganese compounds are the most dangerous components of solid component of welding fume (SCWF) in welding of low-alloyed carbon steels. Toxicity of these compounds, in turn, depends on manganese valence and increases with a rise of its oxidability.
A series of investigations, dedicated to study of SCWF chemical composition showed that Mn2+ and Mn3+ are the most possible states of manganese. Investigations of valent state of manganese in the fumes formed in welding with basic and rutile types coated type electrodes were carried out by researchers of the E. O. Paton Electric Welding Institute and I. M. Frantsevich Institute of Problems of Materials Science of the NAS of Ukraine. The investigations were carried out with the help of X-ray photoelectron spectrometer (XRPES) ES-2401.