COMPOSITION OF CHARGE OF SELF-PROTECTING POWDER WIRE Russian patent published in 1995 - IPC

FIELD: welding practice, particularly composition of charge of self-protecting powder wire for welding thick-plate structures from low-carbon and low-alloy steels. SUBSTANCE: relation of total content of fluorine in fluorspar and sodium silicofluoride to iron powder is 0.12 - 0.14, relation of fluorspar to sodium silicofluoride , 2.4-4.0 at the following ratio of components, wt.-%: iron powder, 60-65; fluorspar, 11-13; marble, 5-8; sodium silicofluoride, 3-5; ferromanganese, 2-3; ferrotitanium, 1.5-2; ferrosilicon, 15-2; aluminium powder, 1.5-2; rutile, the balance. Said composition of iron powder ensures radical increase in the arc energy intensity while narrowing of arc column is ensured by intensive gas protection with fluorine. EFFECT: higher impact strength of weld metal due to a smaller area of weldpool spot and its isolation from nitrogen and hydrogen of atmospheric air. 2 tbl