Property and Productivity Improvements in Electroslag and Electrogas Welding.

摘要

An apparatus has been developed for automated vertical welding in the electroslag and electrogas modes with addition of metal powder filler. Metal powder is dispensed in combination with shielding gas through a ceramic nozzle to the welding electrode where electromagnetic forces hold it in place and convey it to the weld pool. Welding tests using the new process have been performed on ABS Grades B and AH 36 plate. Both flux-cored and metal powder- cored electrodes were evaluated in the electroslag and electrogas modes. Solid electrodes were evaluated in the electroslag mode. Welding parameters found to be satisfactory for each mode of operation are presented. A detailed evaluation of weldment mechanical properties for procedures employing metal powder filler is presented. Premiminary results of the metal powder-bearing fluxes and ceramic backing tapes in electroslag welding with metal powder filler additions are presented. Significant increases in welding process productivity have been realized through the use of metal powder filler in both the electroslag and electrogas processes. Productivity is found to increase in direct proportion to the amount of metal powder added. Mechanical property evaluations of welds produced in ABS Grade B plate with metal powder filler additions show the effect of such additions to plate show mixed results in observed in some welds when heat input were observed in dimensions and grain size. be beneficial. Welds produced in ABS Grade AH 36 plate show mixed result in that a degradation of mechanical properties was metal powder was observed in some welds when metal powder was added. Reductions in process heat input were observed in all welds as shown by reduced heat affected zone dimensions and grain size.