SPOT-WELD JOINT AND METHOD FOR SPOT WELDING Russian patent published in 2017 - IPC B23K11/11 B23K11/16 

FIELD: metallurgy.

SUBSTANCE: value of the carbon equivalent of Ceq of a high-strength steel sheet is 0.20 to 0.55 wt %. In the heat-affected area in a square region, which one side length is 10 mcm, there are ten or more grains of iron-based carbides, the length of the longest part of each of which is not less than 0.1 mcm. The joint is made by the main welding when applying current to the welding electrodes in the state of compression of superimposed steel sheets, cooling the steel sheets after completion of the main welding while maintaining the compression force and re-applying to the welding current electrodes.

EFFECT: improving the peel strength of the spot-weld joint.

3 cl, 12 dwg, 8 tbl