In order to perform bending test with re-bending, the steel sample is first bent by 90°. The diameter of the mandrel on which bends can be made are strictly defined in the standard and are - depending on the diameter of the rod under test - from 4d to 8d (where d - the diameter of the rod under test). Subsequently, the sample is aged, i.e. heated to 100° C, kept at this temperature for one hour and then cooled to room temperature in natural conditions. In the last step, the sample is deflected by an angle of min. 20°. If no damage visible to the naked eye appears on the surface of the sample, it is considered that it has passed the bending test with deflection positively.
A bending test with a static tensile test is performed for bars with a diameter of d 16 mm. It consists in bending the rod by 90° (while maintaining the requirements as in the bend test with bending), and then straightening and subjecting to a static tensile test. The condition in this test is that the test sample meets the basic required strength and strain properties: Re, Rm/Re, A5 and Agt.
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