軟鋼心線の熔接性と被覆熔接棒の性質との関係

Abstract

The author studied some time ago on the weldability of electrode core and found that weldability was seriously affected by the non-metallic inclusions rather than by the chemical constituents such as C, Si. Mn etc. He discussed further how the melting process for the core should be operated.He has since been trially making middle coated electrodes with cores of different weldabilities. It has been confirmed through the experience that the properties of electrodes consist of algebraic summation of its core and flux; substantial quality improvement of the electrode with a core cannot be effected only by adjusting the flux composition.As an example for the standard mild steel core, tension tests of deposited metals obtained by poor cores gave merely 28-30% elongations, but the tests with those by good cores showed the maximum values of 37%.On the other hand, the tests by pure iron cores of good quality produced up to 40% elongations. Besides, the author investigated arc-stability, bead-appearance and degree of fillet crack etc., with the conclusion reached that the quality of core affected seriously the quality of electrode, namely that it was necessary to use core having excellent weldability to the end of obtaining the superior quality of-electrode.Finally production of such electrodes was accomplished with the use of the Hitachi M flux composition.