3-Point Bend Testing
Why 3-Point Bend Testing?
Elastic modulus in bending (i.e., flexural modulus), stress-strain behavior, and failure limits in bending all can be obtained using the simple sample geometry of a 3-point bend test. ASTM D790 or ISO 178 covers flexural properties for plastics; ASTM E855 is used for properties of flat metallic spring materials; ASTM C1684 or C1161 covers 3-point bend testing of ceramics.
在三点弯曲试验,凸的她et or plate is placed in tension, and the outer fibers are subjected to maximum stress and strain. Failure will occur when the strain or elongation exceeds the material’s limits.
可以使用三分弯曲测试来确定断裂韧性。在这种情况下，可以使用预注册的样本，并且可以遵循ASTM E-1290或ISO12135的过程。可以使用ASTM D7774获得疲劳特性。对于医疗应用，ASTM F2606用于对球囊张开的血管支架和支架系统的三分弯曲测试。
Easy-to-Use 3-Point Bend Tester
Bruker’sUMT Tribolabcan be equipped with an easy-to-use 3-point bend module for assessing various properties of laminate and sheet materials. Tests can be run under load-displacement-control modes.
Use of Acoustic Emission in 3-Point Bend Tests
In the case of composite materials, failure can occur due to delamination between the fibers and the matrix, prior to complete specimen failure. While this can sometimes be seen in the stress-strain curve data, it can also be detected using an acoustic emission (AE) sensor, and with much higher sensitivity. Failure criteria thus can be defined as the first indication of fiber delamination or breakage, the onset of significant AE signal, or the rise to a specific pre-defined level of AE.
The optional AE sensor can be used to assess a number of composite research areas, including surface activation of the fibers, wetting chemistry of the matrix, and fiber surface roughness characteristics.
