アルミニウム合金突合せ溶接継手の自由曲げ試験
1976 年 26 巻 3 号 p. 139-149
詳細
1976 年 26 巻 3 号 p. 139-149
The free-bend tests were carried out on the butt-welded specimens of aluminum alloy 5083-0 with thickness of 22 and 50 mm, and on 5083-0 plate specimens with various thickness. Changes in the strain distribution with an increase in the bend angle were measured and cracks appeared on the convex face of the specimen were examined. The principal results obtained are as follows.
1) The maximum bending strain measured for a given bend angle increased with an increase in thickness of specimens.
2) The maximum bending strain depended on tested materials even if the specimen thickness and the bend angle were kept constant.
3) The method shown in Fig. 8 (a) is recommended for initial bending prior to the free-bend test.
4) Cracks appeared at the smaller bend angle and at the lower maximum bending strain as thickness of the specimen increased.
5) The elongation values, measured by gauge lines marked on the tension side of the weld, were very little affected by variation of gauge length.
6) The required elongation in the free-bend test for butt-welded joints of 5083-0 may be about 15-20% to assure the same ductility obtained in the side-bending test of the specimen with R/t of 3.3 where R is the punch radius and t is thickness of the specimen.
