Particle size distribution of welding fume and its dependency on conditions of shielded metal arc welding

•The subject of study is the arc welding fume formed when the electrodes with rutile and carbonate-fluorite covers are applied.•The particles size distributions are measured by the laser aerosol spectrometer.•The three-modal distribution of the welding fume particles is found out.•The welding factor determining the particles size is the product of the arc resistance, the wire feed rate and the electrode sectional area.

The particle size distribution of the shielded metal arc welding fumes is studied. The laser aerosol spectrometer and optoelectronic aerosol counter with the total measurement range of 0.15-10 μm were used. It is demonstrated that the number-based size distribution is described by the three-modal lognormal distribution, where the first two modes are the result of the liquid-phase and solid-phase coagulation and the third mode is the coarse fume particles. The linear dependency of the average size of the particles on the product of welding parameters: the arc resistance, the wire feed rate and the electrode sectional area is revealed.