EFFECT OF WELDING PARAMETERS ON SURFACE DEPOSITION CHARACTERISTICS OF SUBMERGED ARC WELDS USING STRIP ELECTRODES

Abstract

In the present investigation, a study has been made to assess the effect of welding parameters on the weld deposit characteristics in a single pats submerged-arc strip overlay (cladding) process. Weld deposits were made on 15 mm thick mild steel base metal using a" 60 x 0.5 mm L21/10 stainless steel strip with neutral flux LW-410. The effect of welding current, arc voltage and travel speed was studied on the ferrite content of overlay surface, bead geometry and dilution. It was found that the ferrite content of the overlay decreased with the increase in all the above three welding parameters. With the increase of these parameters, the penetration and dilution increased. The bead width wa found to increase with the increase of welding current and arc voltage but decreased with the increase of travel speed. Metallographic study revealed the formation of the Widmanst'atten structure in HAZ during cladding on this base me tat. Microhardness measurement in the ferritic region showed the increase of hardness in interface region fusion boundry with the increase of welding .current and arc voltage with a decreasing trend with the increase of travel speed. contd.... Ii After the analysis of a few deposits by a vacuum emission spectrometer, it was found that the use of neutral flux increased the silicon content of the overlay while there was decrease in chromium and nickel level of the overlay. Intergraru1lar corrosion testing of representative specimenswas made by boiling them in Strauss solution for 24 hours and it was found after performing the bend test that they were not susceptible to intergranular corrosion. n