Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1278394 | International Journal of Hydrogen Energy | 2015 | 6 Pages |
•Commercial ZK60 magnesium alloy was processed by ECAP and ARB for hydrogen storage.•Low surface to volume ratio of the ECAP plus ARB samples limits storage capacity.•Faster kinetics and higher storage capacity is produced by pulverization of samples.
The hydrogen storage properties of a commercial ZK60 magnesium alloy were investigated after processing by equal-channel angular pressing (ECAP) and accumulative roll-bonding (ARB). Samples were prepared by 6 passes of ECAP and subsequently rolled 25 times. Microstructural characterization was performed using scanning and transmission electron microscopy. The kinetics of hydrogen absorption and desorption were measured in a Sievert-type apparatus. Processing only by ECAP resulted in a very low hydrogen storage capacity of 0.5 wt. %. Additional processing by ARB refined the microstructure and improved the hydrogen absorption. Despite this improvement, the hydrogen capacity was limited to less than 4 wt. %. This limitation was overcome by crushing the materials into small thin plates. The crushed sample from the ECAP material absorbed 4.77 wt. % of hydrogen in 24 h while the capacity of the sample processed by ECAP and ARB was 6.4 wt. %. The results are discussed in terms of morphology and microstructure of the samples.