Electroslag Welding of Cast Iron (Report 2)

Some investigations on experimentally produced fluxes

Abstract

As described in the last report, it was known that electroslag welding of cast iron can be exected by use of a cored wire(Fe₃C+Fe-Si) and a hollow graphite nozzle. This welding, however, has been somewhat unstable; as one reason for this instability may be mentioned the adoption of commercial flux for mild steel. Since the melting point of castiron is only slightly higher than that of the commercial flux, slag inclusion is liable to happen and the welding results tend to be poor.
Thereupon, with mainly the aim to develop a welding flux that can produce a lower temperature fusible slag, several types of flux were prepared; the electroslag welding ofcast iron plates using them were investigated. Meanwhile, the performances of these fluxes were compared by measuring the physical properties, such as viscosity and electric resistance of welding slag. Furthermore, the dynamic behavior of the molten slag during welding was observed by X-ray inspection. Finally there were discribed the results of repair welding practically applied on defects of large machine tool tables using the flux E6 selected from the results in this study.