| Summary: | Hot compression tests of Mo–1.5 wt% Al<sub>2</sub>O<sub>3</sub>/ZrO<sub>2</sub> molybdenum alloys were carried out using the Gleeble–1500 simulator at 0.01 s<sup>−1</sup>−5 s<sup>−1</sup> strain rates and 1000–1500 °C deformation temperatures. The microstructural changes of the alloy at 1000–1500 °C were studied. The changes in the hot deformation process for the Mo−1.5 wt% Al<sub>2</sub>O<sub>3</sub>/ZrO<sub>2</sub> molybdenum alloys were analyzed by means of EBSD. The ZrO<sub>2</sub> particles had a greater effect on improving the thermal deformation resistance of molybdenum alloys than did the Al<sub>2</sub>O<sub>3</sub> particles. The activation energy of the molybdenum alloy doped with ZrO<sub>2</sub> (403.917 kJ/mol) was lower than that of the molybdenum alloy doped with Al<sub>2</sub>O<sub>3</sub> (440.314 kJ/mol). Due to the occurrence of recrystallization, the intensity of {100} the texture first increased and, then, dropped down with increase in the temperature, while the change law of {111} texture was the opposite. Above 1200 °C, the higher deformation temperature made the texture more random by lowering the texture intensity. The dislocation density was sacrificed to promote recrystallization. When dynamic recrystallization occurred, the sub–grain boundaries absorbed dislocations and transformed them into high–angle grain boundaries, resulting in a decrease in dislocation density and an increase in high–angle grain boundaries at high temperatures and low strain rates. At 0.01 s<sup>−1</sup> strain rate, the average grain size of Mo–1.5 wt% ZrO<sub>2</sub> alloy increased from 2.38 μm to 4.67 μm, and the proportion of large angle grain boundaries increased from 59.8% to 86.6%.
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