The article presents the research results of fume morphology derived from arc welding of stainless steels of 1.4301 and 1.4828 grade. The analysis was performed using laser diffraction and high-resolution scanning electron microscopy. Welding fume has been classified by the International Agency for Research on Cancer (IARC) as a group of agents with proven carcinogenic effects to human. The assessment of the risk related to exposure to welding fume emission depends on the amount of fume generated, its chemical composition and morphology. The combined analysis of these factors determines the toxicity of fume and its impact on the human body. The results of the fume particle size distribution and the analysis of the shape and chemical composition using SEM with EDS in connection with the determination of the fume emission rate enable to obtain an overall assessment of the health risk as-sociated with welding fume. Such assessment is particularly important during welding processes of corrosion-resistant steels, due to the presence of chromium and nickel compounds in the fume, which are classified as substances with proven carcinogenic effects to human (Group 1 according to IARC guidelines). It was found that 15-17% of particles deriving from arc welding belong to the respirable and tracheal fractions, which are the most harmful due to the penetration beyond the larynx.

Stainless steels are widely used across many industrial sectors, including the fabrication of welded structures. The most common methods for joining these materials are arc welding processes. Increasing demands for higher weld quality and process efficiency have led to a growing adoption of laser-based technologies in industry. One of the most frequently applied techniques is hybrid laser–arc welding (HLAW), which combines two heat sources—the laser beam and the electric arc—acting simultaneously. For new, innovative joining technologies, a critical factor in their implementation is their impact on the environment and human health. This article presents the results of a study on the morphology of fumes emitted during the HLAW of X5CrNi18-10 (1.4301) stainless steel. Laser diffraction and scanning electron microscopy were used to characterize the fume morphology. The International Agency for Research on Cancer has classified welding fumes as a carcinogenic agent to humans. The results revealed that more than 20% of particles generated during hybrid welding belong to the most hazardous fraction, as they can penetrate beyond the laryngeal region. These particles exhibit a homogeneous elemental distribution, with the chromium content standing at approximately 20% and nickel nearly 10%.

Fume morphology is the science of the structures, forms, shapes, fractions, and chemical composition of particles