Study on HIx cycling techniques for thermo chemical hydrogen production process. R and D on refractory and corrosion resistant pressure sensor for hydrogen iodide cycling test loop

High refractory and corrosion resistant pressure sensor with tantalum/SUS 316 welding type diaphragm has been developed for hydrogen iodide cycling test in thermo chemical hydrogen production process and tested its fatigue and corrosion properties. With these results, the following conclusions were derived. (1) New type of high refractory and corrosion resistant alloy was found in Ta/SUS 316 welding region and its elemental composition was identified as 83Ta-11Fe-2Ni-2Cr-2Mo [wt.%]. (2) This pressure sensor achieved a new record of the longest fatigue life over 107 cycles within 0.44%F.S./degC and (3) No degradation of its mechanical and sensitivity properties was found after 20000 hours hydrogen iodide cycling test. (author)