What is a bend test and what does it assess?

What is a bend test and what does it assess?

• A. A mechanical test bending a welded coupon to check ductility and detect cracks at the weld.
• B. A chemical test to determine composition.
• C. A test to measure surface roughness.
• D. A test to check color of weld.

Answer: (A)

A bend test is a mechanical evaluation of a welded joint’s ability to deform without cracking. A welded coupon is bent over a former to a specified angle (often around 180 degrees) to stress the weld and the heat-affected zone. If the weld is ductile, it will bend with the base metal and show no cracks in the weld or HAZ. If there are issues with ductility or defects like lack of fusion, porosity, or inclusions, cracks will appear at the weld or in the heat-affected zone. This test directly checks the weld’s structural soundness under bending, which is why it’s used in qualification and quality control. It isn’t about chemical composition, surface roughness, or color, which are assessed by other means.

A bend test is a mechanical evaluation of a welded joint’s ability to deform without cracking. A welded coupon is bent over a former to a specified angle (often around 180 degrees) to stress the weld and the heat-affected zone. If the weld is ductile, it will bend with the base metal and show no cracks in the weld or HAZ. If there are issues with ductility or defects like lack of fusion, porosity, or inclusions, cracks will appear at the weld or in the heat-affected zone. This test directly checks the weld’s structural soundness under bending, which is why it’s used in qualification and quality control. It isn’t about chemical composition, surface roughness, or color, which are assessed by other means.