Influence of annealing process on microstructure and purity of WTi10 target

To optimize the microstructure and purity of the WTi10 sputtering targets, the subsequent annealing process was treated without changing the initial hot pressing conditions. The microstructure, grain size, and purity of the samples were observed and measured by Keyence microscope, scanning electron microscope, and glow discharge mass spectrometer (GDMS). The results show that, with the increase of annealing temperature, the Ti-rich β1(W, Ti) phase gradually decreases, and the W-rich β(W, Ti) phase gradually increases. When the annealing temperature is lower than 1200 ℃, the materials consist of the W matrix with the W-rich β(W, Ti) phase and the Ti-rich β1(W, Ti) phase. A further increase in annealing temperature to 1700 ℃ results in a remarkable change in phase composition, leading to the disappearance of the Ti-rich β1(W, Ti) phase, which approaches a uniform recrystallized microstructure with an average grain size of 7.9 μm, meanwhile, the oxygen mass fraction of the samples is 0.041% and the purity is 99.995% above.