The invention discloses a method for measuring temperature in a reactor based on SiC
thermal expansion coefficient change after
neutron irradiation. The method comprises the following steps: S1,
processing a SiC
crystal material into a sample with a columnar structure; s2, packaging the SiC
crystal sample and the to-be-irradiated material sample into an
irradiation sample box, and putting the
irradiation sample box into a reactor for a
neutron irradiation experiment; s3, after the
neutron irradiation experiment is completed, taking out the irradiation sample box from the reactor,
cutting and disassembling the irradiation sample box, and then taking out the irradiated SiC
crystal sample; s4, putting the SiC crystal sample into
thermal expansion measurement equipment, and measuring the change of the elongation of the SiC crystal sample along with the
gradual increase of the temperature; and S5, calculating the change rate of the elongation of the SiC crystal sample gradually rising along with the temperature, and drawing a change curve of the instantaneous
thermal expansion coefficient of the SiC crystal sample along with the temperature to obtain the
neutron irradiation temperature of the position of the SiC crystal sample in the reactor.