Abstract:This paper studied a new process for preparing high-purity fine-grained niobium tube target materials, in order to obtain niobium tube target materials with small and uniform structure. Firstly, high-purity niobium ingot of Φ 300 mm diameter was forged and vacuum annealed, and then, it is processed into extruded ingot through turning and drilling, The hole in the ingot was enlarged on the hot perforating machine from Φ 65 mm to Φ 93 mm, extruding into niobium tube target on the extruding machine after heating. High-purity niobium tube target products were obtained after vacuum annealing and mechanical processing. The metallographic test results show that the niobium tube target product has fine and uniform grain size, the average grain size is 38 μm in the horizontal direction, and 32 μm in the vertical direction. The electron back scatter diffraction (EBSD), test results show that the texture of the extruded niobium tube target product is mainly composed of <001>, the texture of the recrystallized niobium tube target product is mainly a mixed texture composed of two components: <110> and <111>.