Optimizing the content of nickel in flux-cored wire intended for welding micro-alloyed steels

Abstract

This paper presents the results related to organizing production of flux-cored wire alloyed with Ni and Mo according to standard AWS A5.29 intended for the MAG welding process. On the experimental line for steel strip calibration and production of flux-cored wire two batches of flux-cored wire were produced with a constant Mo and Ni content at two levels (1.2% Ni in one and 2.6% Ni in the other batch). Experimental welding of steel plate samples was performed using the MAG process with two qualities of cored wire. Testing the structure and quality of the weld metal was done in order to optimize content of Ni in the alloyed flux-cored wire intended for welding fine grained micro-alloyed steels. Based on the analysis of test results of the microstructure and EDS analysis of the structure of welded samples and test results of tensile properties and impact energy, conclusions were made about the optimal content of Ni in the weld metal, and thus the choice of quality of flux-cored wire.

U radu su dati rezultati vezani za osvajanje proizvodnje punjene žice legirane sa Ni i Mo prema standardu AWS A5.29 namenjeno za MAG postupak zavarivanja. Na eksperimentalnoj liniji za kalibraciju čelične trake i izradu punjene žice proizvedene su dve šarže punjene žice sa konstantnim sadržajem Mo i sadržajem Ni na dva nivoa (1.2%Ni kod jedne i 2.6%Ni kod druge šarže). Eksperimentalno zavarivanje uzoraka čeličnih ploča je izvedeno MAG postupkom sa dva kvaliteta punjene žice. Ispitivanje strukture i kvaliteta metala šava je izvedeno u cilju optimizacije sadržaja Ni u legiranoj punjenoj žici koja je namenjena za zavarivanje sitnozrnih mikrolegiranih čelika. Na osnovu analize dobijenih rezultata ispitivanja mikrostrukture i EDS analize strukture zavarenih uzoraka i rezultata ispitivanja zateznih karakteristika energije udara, dati su zaključci o optimalnom sadržaju Ni u metalu šava, a time i izboru kvaliteta punjene žice.