Optical fiber sensing measurement device and method for low-temperature thermal expansion coefficient of material

The invention discloses an optical fiber sensing measurement device and method for a low-temperature thermal expansion coefficient of a material. The device comprises a low-temperature environment simulator, a platform, a microcrystalline flat crystal, a thermal resistor, a heating sheet, a zero-expansion substrate, an optical fiber sensor and a clamping tool of the optical fiber sensor. A zero-expansion substrate is placed on a platform of a low-temperature environment simulator, a thermal resistor and a heating sheet are pasted on a tested sample piece, microcrystalline flat crystals are pasted at two ends, and the tested sample piece is fixed on the zero-expansion substrate. The optical fiber sensor probe is fixedly installed on the zero-expansion substrate and right faces the two end faces of the sample piece. The temperature is controlled from normal temperature to low temperature and then to normal temperature through the low-temperature environment simulator, and in the double processes of temperature