Some Key Problems in Testing of Ductile-Brittle Transition Temperature of Metallic Materials

Some problems encountered in the testing of the ductile-brittle transition temperature of metallic materials and corresponding solutions were discussed. The results show that when processing the test data, the fitting functions would have a great influence on the final test result, and the fitting results with Boltzmann function were more practical. The four methods for determining the ductile-brittle transition temperature had their own characteristics, and they should be applied flexibly according to the actual situation. Specimen crystal area profile, fracture flatness, especially the ductile brittle fracture section type would directly affect the evaluation of percent shear fracture, and the sampling location and direction should be indicated in the test report. When the number of specimens was limited, specimens should be allocated in a reasonable range with percent shear fracture of 30%~70% to obtain the ductile-brittle transition temperature.