Abstract
Both the contents of oxygen and nitrogen in the weld metal which were obtained by the submerged arc welding with various welding speeds in the argon atomsphere and the influence of the gas contents on the impact values of those weld metals were investigated.
The results obtained are summarized as follows.
(1) The oxygen content in the weld metal increases as the welding speed increases, and the oxygen content in weld metal is given by the following formula.
O=MVx
Where O: Oxygen content in weld metal (ppm), V: Welding speed (cm/min), M, X: Constant.
(2) The Si, Mn and C contents approach the calculated values (the average values of the consumed wire parts and the molten steel plate parts) as the welding speed increases.
(3) The nitrogen content in the weld metal is almost constant irrespective of the welding speed.
(4) The absorbed energy by the charpy impact test decreases as the welding speed increases, and this is given by the following formula.
E=KV-n
Where E: Absorbed energy (Kgf-m), V: Welding speed (cm/min), K, n: Constant.
(5) The weld metal obtained in the argon atmosphere had higher oxygen content and lower nitrogen than those obtained in the air.
(6) In average, the absorbed energy of the weld metal obtained in the argon atmosphere were similar to those in the air with some exceptions.
