Abstract
The work presents a study on temperature changes during tensile tests of high-strength dual-phase steel, performed with different strain rates, •ε₁ = 3.3 x 10^–3 s^–1 and •ε₂ = 33 s^–1, at room temperature, making use of a high-resolution thermographic camera. It has been shown that with increasing strain rate the ultimate tensile strength grows, from ca. 1305 to ca. 1326 MPa, whereby the average strain values decrease from ca. 7.9 to ca. 7.2 %. The temperature of the specimens stretched with the lower strain rate grows during the tensile test by about 32 °C, whereas, in the case of the specimens stretched with a higher strain rate, by about 98 °C. Moreover, the precise analysis of the temperature profiles, registered with the thermographic camera, indicated a significant temperature drop preceding the rupture of specimens by about 5 % of the maximum temperature value.

Key words
thermographic measurements, infrared camera, tensile test, high-speed deformation, dual-phase steels

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