Measurement of vessel strain during hydride formation

G. MEYER; A. BIASETTI; E.M. BORZONE; J. MARÍN; A. BARUJ

Camboriu, Brasil

Congreso; XVIII Brazil MRS Meeting; 2019

Brazilian Materials Research Society

Several investigations are oriented towards the development of a HydrogenEconomy to overcome the environmental problems derived from the use of fossilfuels. Hydrogen is a clean and renewable fuel with a high energy densitycompared to conventional energy sources. The use of hydride forming materials(HFM) is a promising way to solve many problems related to hydrogentechnologies. These materials allow hydrogen to be stored reversibly. The cellvolume of a hydride phase is about 20% greater than the former material.Hydride formation/decomposition cycling converts the HFM in a fine powder thatis compacted at the bottom of the container that contains it. So, the vesselscontaining HFM have to be designed not only to resist internal gas pressure butalso stresses generated during hydriding. In this work we present the study ofstrain and stress on the walls of a vessel containing a HFM. We designed andbuilt an aluminum reactor where we attached 8 strain gages. The reactor wasfilled with 17 g LaNi5 . During activation and the following 20absorption/desorption cycles strain on different points of the vessel wasmeasured. Hydride fraction and wall strain were correlated to observe theevolution and final state. The study of activation, decrepitation and compactionprocess was completed with images obtained using the neutron imagingtechnique of the vessel: empty, initially filled with HFM and filled with HFM after all the cycling stages.