Bending test is a simple qualitative test that can be used to evaluate both the ductility and soundness of a material. This test uses a coupon that is bent in three points to a specified angle over a given radius.

The outside of the bend is extensively plastically deformed so that any defects in, or embrittlement of, the material will be revealed by the premature failure of the coupon. The bended sample is thus inspected for cracks on the outer surface.