Bending Deflectometers for ISO 178, JIS K 7171, and ASTM D790 Compliant Testing
After tensile testing, flexural tests are the most common strength tests for plastics and other resins. The main standards for plastic flexural (bend) tests are ISO 178, JIS K 7171, and ASTM D790, which require very accurate test systems. These standards include flexural strain measurements using a deflectometer, ranging from micro-strain measurements in the elastic region, the reversible elongation at the beginning of tests, to larger strain measurements in the plastic region. Shimadzu's deflectometers integrate easily into AG-X plus series, AGS-X series, and EZ-X test frames and Trapezium X testing software. Since these deflectometers push up against the specimen from below, the specimen color is not a limiting factor, as can be for laser type non-contact deflectometers. Furthermore, these deflectometers can partially absorb the shock during specimen failure, preventing specimen fragments from scattering.
Shimadzu's deflectometers meet the accuracy requirements of ISO 178, JIS K 7171, and ASTM D790. In particular, ISO 178 and JIS K 7171 require demanding displacement measurement accuracy within ±1% of the indicated value throughout testing and flexural modulus measurement accuracy to within ±3.4 μm (for a 4 mm thick specimen).