METHOD OF OVERLAPPED WELDING SECTION, METHOD OF MAKING OVERLAPPED WELDED ELEMENT, OVERLAPPED WELDED ELEMENT AND AUTOMOBILE PART Russian patent published in 2017 - IPC B23K11/10 B23K11/16 B23K26/20 

FIELD: manufacturing technology.

SUBSTANCE: invention can be used for production of parts, in particular, automobile ones, containing multiple steel sheets jointed overlapped by point contact welding. Laser radiation is directed at the core of a point weld section obtained by contact welding to make a section crossing the core and extending beyond its limits by not less than 3 mm. In the steel sheet containing a martensite structure, provided is the depth of the section from the effect of laser radiation measured at the distance of 1 mm from borders of the core of the point weld section of at least 50 % of the said sheet thickness. When connecting the steel sheets, the outer of which is a zinc-plated steel sheet, laser radiation is directed from the side of the uncoated steel sheet to make a section crossing the said core and extending beyond its limits, without melting the section of contact with the zinc-plated sheet. In the uncoated steel sheet provided is the depth of the section from the effect of laser radiation measured at the distance of 1 mm from borders of the core of the point weld section of at least 50 % of the said sheet thickness.

EFFECT: invention ensures prevention of destructions at the sections obtained by contact point welding.

7 cl, 15 dwg, 4 tbl