Displacement Measurement Sample Clauses

Displacement Measurement. Extensometry and strain gauging which measure the deformation of the indentation in a continuous way may be used if they are suitably calibrated and applied in accordance with good testing practice and the manufacturer’s instructions. The displacement of the indentation deformation should be continuously recorded and monitored. The recorded maximum total indentation deformation (occurring at the end of the test) can be checked by measuring the depth of indentation after the test. The opportunity can also be used to identify any wear on the indenter. The use of a laser microscope can improve the accuracy of this process. Using an example from one of the laboratories, the deformation measurement system adopts a loading arrangement similar to that used for a uniaxial creep test. The specimen fits between the indenter and an anvil that replicate a uniaxial specimen. The extensometer is located on the reproduced knife ridges. Two water cooled LVDTs measure the movement of the extensometer and hence indentation depth, outside the furnace. The signal from the LVDTs is averaged by the signal conditioning system on the Xxxxx machine and recorded on a data logger. The measuring range of the extensometers is +/-0.2mm with an accuracy of +/-0.5%.