The Development Of A New Kind Of E308Stainless Steel Electrode And Research On Its Welding Performance

E308stainless steel electrode is one of the most widely used electrodes, which applied to normalchemical equipment, nuclear power industry, war industry, space industry, health and medicineindustry, etc. However, the domestic E308stainless steel electrode still exists a gap in comparisonwith that of the developed countries. In order to improve the welding operation performance of thedomestic E308stainless steel electrode, the paper has optimized the TiO2-SiO2-CaO slag system anddeveloped a new kind of E308stainless steel electrode. At the same time, the paper has carried onsystematic research and discussion around coating composition influences on welding arc stability,pore sensitivity droplet, transfer formations, slag covering ability and detachability, the coating crack,and the corrosion resistance of the E308stainless steel electrode.The influences of coating composition on arc stability of E308stainless steel electrode werestudied through collecting the welding electric signal, analyzing the electric signal, observing the arcshape by high-speed photography. The results showed as the cryolite content increases, welding arcstability turned better at first, but become worse when the content had passed10%wt; Welding arcstability gets better as the feldspar content rised. Considering all the influences worked on theelectrode, when the cryolite is10%wt and feldspar is14%wt, the electrode shows better welding arcstability.The sensitivity of weld porosity were investigated by stomatal sensitivity test. The resultsshowed that both cryolite and the feldspar contributed to decreasing the sensitivity of weld porosity,however the effect of cryolite is stronger the feldspar. When the cryolite is10%wt and feldspar is14%wt, the sensitivity of weld porosity is low while there is no pore in the weld surface.The effects of coating composition on droplet transfer formations of E308stainless steelelectrode and welding spatter generation mechanism were investigated by high-speed photography,collecting droplets and spatter test. The results showed that when the content of cryolite increased, thedroplet got smaller, the transfer generation turned from particle transfer to spay transfer, but generatedmore spatter; The feldspar thining the droplet seriously, the transfer generation turned from particletransfer to flux wall guided transfer while the spatter got less. The optimizing content is10%wtcryolite and14%wt feldspar.The paper has investigated the coating composition influences on slag covering ability by slagcovering ability evaluating and slag detachability testing.The results showed that cryolite improved the slag detachability and made the slag cover more even. So did the feldspar. When the cryolite ismore than5%wt and the feldspar is more than10%wt, the slap can detach completely.The corrosion resistance was studied by electrochemical experiments which get the TafelCurve.The results showed that the cryolite corrosion resistance got a little worse because the alloytransfer efficiency reduced.The feldspar enhanced the corrosion resistance by strengthening thesiliconized reaction. The perfected content range is5%wt to10%wt cryolite and10%wt to14%wtfeldspar.Finally, the paper has acquired the composition for the E308stainless steel electrode withfavorable welding operation performance, i.e. cryolite is (10%), feldspar is (14%).