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The effect of molten salt on oxygen removal from titanium and its alloys using calcium

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Abstract

The sensitivity of titanium to increasing oxygen content and the high cost of reducing oxygen content in titanium have prevented its broader applications. Here we report a low-temperature de-oxygenation process, which can remove oxygen from titanium powders to less than 1000 ppm from original oxygen levels of over 20,000 ppm. The effect of molten salt on de-oxygenation was investigated in this study. The calcium halide-bearing molten salt facilitates the dissolution of solid calcium and creates a metal-molten solution condition by forming intermediate Ca+ ions and finally Ca2+ ions and electrons (e ). The molten salt enables the de-oxygenation of Ti at temperatures lower than the melting point of calcium. It will be shown that the de-oxygenation temperature can be as low as 873 K (600 °C).

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Acknowledgement

This research was supported by the METALS program from Advanced research Projects Agency (ARPA), the U.S. Department of Energy (DOE) under Contract Number DE-AR0000420.

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Correspondence to Zhigang Zak Fang.

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Xia, Y., Fang, Z.Z., Sun, P. et al. The effect of molten salt on oxygen removal from titanium and its alloys using calcium. J Mater Sci 52, 4120–4128 (2017). https://doi.org/10.1007/s10853-016-0674-1

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  • DOI: https://doi.org/10.1007/s10853-016-0674-1

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