ASTM E290, ISO 7438, and JIS Z2248 describe the requirements for
bend testing for ductility of metallic materials. The bend test helps provide a visual indication of the ductility of the material. The guided bend test method requires the specimen to be loaded at its center point with a mandrel or plunger while being supported at the ends. The specimen is bent to a predetermined angle or until the specimen fractures. The convex side of the specimen is visually inspected for cracks or defects, and ailure is determined by the size of the cracks and imperfections allowed by the material specification.
For this test, we recommend using a SATEC Series KN, DX, or HDX model with a W-6810 test fixture. This fixture allows for adjustment of the support span and is supplied with various sizes of loading mandrels to accommodate different specimen thicknesses. The loading supports are held together with two tie rods to provide extra stiffness during loading. The DX or HDX Model dual test space load frames allow the bend test fixture to be positioned in the lower compression test. Any tensile testing can also be accomplished in the upper tensile test space.
Materials testing software packages include bend applications that offer simple test set up and ease of operation when running this type of guided bend test. The software will generate real-time loading curves and can automatically end the test when the target bend is achieved or when the specimen fractures completely. Our advanced control electronics offer the best in responsiveness, data accuracy, and resolution. Additionally, digital calipers can be interfaced with the testing system for push button input of crack measurements.