It is also called bending strength. It refers to the ability of materials to resist bending moment without failure, and is an important performance parameter of materials under bending moment. The ratio of the maximum bending moment of the specimen to the bending section coefficient W during the bending test can be used to represent the maximum normal stress on the tensile side surface of the specimen during bending. Because the stress state of the tensile side of the specimen in the bending test is similar to that of the tensile specimen, the bending strength (i.e. fracture strength) of brittle materials that are not easy to process is usually measured by the bending test. For plastic materials, due to a large amount of deformation, the sample will not bend fracture. At this time, the bending test is not to measure bending strength, but to compare the plastic deformation performance of various materials under certain bending conditions, or to identify the surface quality of parts. It is a type of performance test.
Fundamental of Material Science -> Performance basis of materials