Microstructure evolution of 1073 K extruded U–10Zr (wt. %) fuel during thermal cycling (303–1073 K with a ∼9 hour hold at 873 K during cooling) was investigated using in situ neutron diffraction. Analysis was performed using Rietveld texture and crystal structure refinements from time–of–flight neutron diffraction data, with a focus on the evolution of textures and lattice parameters as a function of temperature. The α–U phase exhibits lattice contraction with increasing temperature along the b lattice direction and lattice expansion in the other directions while the other phases exhibit lattice expansion with temperature in all directions. Contrary to the established phase diagram, the β–U phase is absent at the temperatures of the thermal cycling. (001)_α and (110)_γ plane normals are observed with a strong preferred orientation along the extrusion direction. The variant selection of (001)_α||(110)_γ is observed for the first time.

使用原位中子衍射研究了热循环（303–1073 K，冷却过程中在873 K下保持约9小时）中1073 K挤压的U–10Zr（wt。％）燃料的微观结构演变。使用飞行时间中子衍射数据进行的Rietveld纹理和晶体结构细化进行了分析，重点是纹理和晶格参数随温度的变化。α–U相随b晶格方向的温度升高而晶格收缩，而在其他方向上晶格膨胀，而其他相随温度在所有方向上晶格膨胀。与已建立的相图相反，在热循环温度下不存在β–U相。（001）_α和（110）_γ沿挤出方向具有强烈的首选方向的平面法线被观察到。首次观察到（001）_α ||（110）_γ的变体选择。