Travelling Phenomena of Rotational Plane during Friction Welding

Experimental Results and Travelling Mechanism

Abstract

In general, the rotational plane (the friction plane) and the metal boundary plane (the press-welded plane) during friction welding have been considered to be identical. Anthers have found the travelling phenomena of the rotational plane that the rotational plane and the metal boundary plane are not identical in some combinations of dissimilar material specimens and in some combinations of similar material specimens with different diameters welded under the friction welding conditions which include conventional welding conditions, moreover the distance between the rotational plane and the metal boundary plane increases as the heating time increases, and reaches a saturated value.
In this report, some examples of the travelling phenomena of the rotational plane are shown, then effects of welding conditions and of variations in specimen diameters on the travelling distance of the rotational plane are investigated. The travelling phenomena and saturation mechanisms are also discussed.
Main results obtained are as follows:
1) The rotational plane generally differs from the metal boundary plane during friction welding under the friction welding conditions which include conventional welding conditions.
2) The travelling and saturation mechanisms can be qulitatively explained by the plastic deformation resistance of specimens and the temperature distribution in the neighborhood of the rotational plane.
3) The travelling direction of the rotational plane is determined by the quality of specimens and the difference between specimen diameters welded.
4) The travelling distance increases as the heating time and the difference between specimen diameters increase, and decreases as the heating pressure and the rotational speed increase.