From the investigations of the mechanical properties of Veed butt joints which were welded with the coated electrode the wire of which had different coefficients of drawing, the author found out that there was a certain relation between the coefficient of drawing and the mechanical properties of welded joint:
If the coefficient of drawing lays within the range of 55-70%, the amount of blowholes in the deposit decreases to the minimum, And it is noteworthy that, using the wire annealed at 750°C, this phenomenon, especially when drawn in the range above mentioned, reaches to a remarkable degree. That the tensile strength and the elongation of welded joint are, as a rule, inversely proportional to the amount of blowholes, is here also proved true. Therefore as a wire to be used in electric welding, the author recommends, as far as this experiment concerns, to choose the annealed one which is initially drawn in 55-70%.
Cold free bend test is not suitable, it seems, to find out such a delicate matter as the present object repuires. In fatigue test, the conclusion could not be obtained, on account of carelessness in preparing the specimens. But as the result indicates that the drawing and annealing of wire may have certain effects on the fatigue of welded joint, further tests should be clone precisely to obtain the definite conclusion.
抄録全体を表示