Cored welding electrode wires for hard surfacing - using cobalt sheath contg molybdenum, chromium and ferrosilicon powders

摘要

Cored electrode wires, for the hard surfacing by welding of metallic substrates, the novelty being the use of a metal sheath made of a Co-Fe alloy contg. max. 5% Fe, and filled with a mixt. of metal powders meeting the compsn. 54-68% Mo(100% Mo); 30-38% Cr (100% Cr); and 2-8% ferro-silicon (90% Si); and where the wt. ratio metal powders:sheath is between 60-100 and 100:100. The ferro-silicon may be replaced by 5-18% silico-manganese (Si:Mn = 50:50) and the pref. compsns. for the powders are (a) 58% Mo, 35% Cr, 7% Fe-Si, (b) 54% Mo, 33% Cr, 13% Si-Mn. A plasma torch is pref. employed. The deposit obtd. has high hardness, and high wear- and corrosion-resistance; the deposits are free from defects and the outer sleeve of the electrode is ductile.