Research regarding the effect of manganese/sulphur ratio in the weld metal deposit on slag detachability for austenitic stainless steel electrode

The slag removal is one of the most important technological properties of welding consumables. (During time, many attempts have been repeatedly made to improve the slag removal from a bead surface, but no consistent opinion has been established on the correlation between the detachability and chemical composition or/and physical properties of the slag. In some comprehensive investigations high softening and melting point, high coefficient of thermal expansion, fragility or crystalline lattice parameters of slags are re-given as one of the main factors improving slag detachability. It should be noted that these physical properties are of secondary importance if the chemical bond is formed between slag and bead surface. This paper shows that this interfacial tension could be decreased by using a strong surfactant as sulphur in coating formulation combined with the changement of the oxidating potential of the slag. Consequent, a remarkable improvement of the slag removal could be achieved This phenomena was studied for a particulary case - stick electrode E 307 - 15 type - but could be extended also for other welding consumables.