镍基合金受熔融氟化盐腐蚀的同步辐射XRF分析

SR X-ray analysis of Ni-based alloys corroded in molten fluoride salt

采用浸入法在750℃熔融氟化盐(LiNaKF)中进行Inconel 600、Hastelloy X、Hastelloy c-276镍基高温耐蚀合金的腐蚀实验。利用同步辐射微束X射线荧光分析(μ-XRF)及X射线衍射(XRD)对样品进行了分析测试。μ-XRF结果表明,镍基合金在熔融氟化物中的腐蚀主要为合金元素Cr的流失;XRD结果表明,Hastelloy c-276合金中的钼元素在腐蚀过程中形成Mo_2C化合态,该化合态有助于提高镍基合金在熔融氟化物中的耐腐蚀性能。

Corrosion test of Ni-based high temperature alloys of Inconel 600, Hastelloy X and Hastelloy c-276 were performed in molten fluoride salt （LiNaKF） at 750℃ for up to 320 h. The virgin and corroded samples were imaged by scanning electron microscope, analyzed by synchrotron radiation microbeam X-ray fluorescence （μ-XRF） and characterized by X-ray diffraction （XRD）. The μ-XRF results show that corrosion of the Ni-based alloy in molten fluoride salt is mainly due to the erosion of alloying element Cr. The XRD results show that the alloying element Mo of Hastelloy c-276 formed the Mo2C structure, which can enhances anti-corrosive performance of the alloy in molten fluoride salt.