Welded joint bending test is an important index to investigate and evaluate the performance of welded joints, in the welding process test and evaluation, all need to be in accordance with the welding process evaluation standards for bending performance test. For the joint bending test specimen bending method, commonly used to bend the specimen placed in the interval set on the two lower support rollers, and then the upper pressure roller bending way for bending test, to observe the weld without cracks.

Test Principle

A transverse or longitudinal specimen taken from a welded joint is bent without changing the direction of bending, and plastic deformation is produced by bending, causing tensile deformation of the surface or cross-section of the welded joint.

Preparation of specimen

1, position

For butt joints transverse bending test, should be from the product or test piece of the welded joint transversely intercepted specimens to ensure that the axis of the weld after processing in the center of the specimen or suitable for the test position. For longitudinal bending test of butt joints, the specimen shall be taken longitudinally from the welded joint of the product or test piece. The position and orientation of the bending specimen with overlays shall be in accordance with the relevant standards or protocols.

2. Marking

Each specimen shall be marked to identify its exact position in the product or joint. If required by the relevant standards, the processing direction of the specimen should be marked (such as rolling direction or extrusion direction). Each specimen should be marked to identify its exact position in the test piece.

3, heat treatment and / or aging treatment

Unless the relevant standards require or allow the welded joints to be tested to heat treatment, welded joints and specimens do not heat treatment. If heat treatment is carried out, the parameters of heat treatment should be recorded in detail in the report. For aluminum alloys if natural aging is produced, the interval between welding and the start of the test should be recorded.