Study on Metallurgical Reactions in Arc Welding (Report 1)

Deoxidation equilibriums in Arc melting were studied as the first step in the investigation of metallurgical reactions in arc welding. The iron specimens containing oxygen and some deoxidation alloying elementss were melted under arc using a tungsten electrode in an Argon atmosphere, and these deoxidation reactions were investigated.The results of the Si, Mn, Si-Mn, V, Ti, Al deoxidations and the oxygen solubility in pure iron are as follows.(1) Within 100 sec., all the reactions reach the apparent equilibriums.(2) Being compared with the thermodynamical equilibrium data, the results of the apparent equilibriums of the Si ( 0.5%) are very active, and these results can not be interpreted by the SiO2 forming reaction. It is anticipated that the equilibriums will be controlled by the SiO forming reaction at the constant SiO pressure. This a characteristic phenomenon in arc melting.