Presently, the reduction of kerb weight consists in the replacement of previously used structural materials with new ones, characterised by more favourable operating parameters. Advantageous mechanical properties of steel elements are primarily obtained through precise hot treatment performed after cold rolling or, in cases of hot-rolled products, through thermo-mechanical treatment. When subjected to welding, the above-named materials reveal high sensitivity to intense thermal cycles accompanying welding processes. The article presents the results of technological tests concerning the effect of arc weld brazing on the structural and mechanical properties of joints made of multiphase steel CPW 800.