Error Analysis of Measuring Metal Mechanical Properties in High-temperature by Moiré interferometer

The Metal Mechanical Properties have been successfully tested by Moiré interferometer in high-temperature. The grating frequency of metal zero thickness determines the measurement accuracy in this experiment. This paper have discussed the influence of temperature and load to the grating line frequency, and calculated the measurement error. The error caused by thermal deformation is 0.84%, while caused by load is 0.17% for the aluminum alloy on 300 ℃. The error caused by thermal deformation is 1.52%, while caused by load is 0.34% for Ni-Cr alloy on 1 000 ℃. We can conclude that the thermal deformation of temperature is the main factor for the measurement error, and a modified calculation method is also proposed in this paper.