There is a necessity in increase of toughness and ductility indices of weld metal of high-strength low-alloy steels. Effect of inoculants on process of solidification and formation of grains of primary structure is not studied enough. Possibility of regulation of grain size of primary weld metal structure by weld metal melt inoculation with refractory titanium compounds, included into flux-cored wire was considered. Distribution of non-metallic inclusions in weld metal on size and morphology was investigated. Examinations of primary and secondary weld metal structure were carried out. It is determined that entering of titanium refractory compounds into the weld pool allows changing the size of primary structure dendrites. It was found that presence of titanium compounds having poor wetting by liquid iron (TiN) at interface results in blocking of dendrite growth. At the same time, introduction of titanium compounds characterized by small liquid iron wetting angles (TiC), in the melt promotes for formation of coarser dendrites. It was shown that weld metal with bainite (TiN) or ferrite (TiC) secondary structures, which are close on strength indices but differ on ductility and toughness levels, can be obtained depending on inoculant structure. Obtained results are realized in technology for welding of HSLA steels using flux-cored wire with titanium-containing inoculants. Technology has passed experimental-industrial verification at Novo-Kramatorsk Machine-Building Works. 7 Ref., 5 Tables, 5 Figures.

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