  Properties of high entropy alloys are currently in the spotlight due to their
promising applications. One of the least investigated aspects is the affinity
of these alloys to hydrogen, its diffusion and reactions. In this study we
apply high-pressure at ambient temperature and investigate stress-induced
diffusion of hydrogen into the tructure of high entropy alloys HEA including
the famous Cantor alloy as well as less known, but nevertheless important
platinum group PGM alloys. By applying X-ray diffraction to samples loaded into
diamond anvil cells we perform a comparative investigation of these HEA alloys
in Ne and H2 pressure-transmitting media. Surprisingly, even under stresses far
exceeding conventional industrial processes both Cantor and PGM alloys show
exceptional resistance to hydride formation, on par with widely used industrial
grade CuBe alloys. Our observations inspire optimism for practical HEA
applications in hydrogen-relevant industry and technology e.g. coatings, etc,
particularly those related to transport and storage.
