Development of Material Mechanical Properties Testing Platform for Liquid Hydrogen Temperature Zone

Many materials exhibit a ductile-brittle transition as the temperature decreases. Liquefied gas and cryogenic equipment become more and more widely used in the industry, especially the accelerated commercialization of the liquid hydrogen industry. However, there is a lack of cryogenic mechanical property testing platform and published material mechanical property data below the liquid nitrogen temperature zone (77K). The development of cryogenic mechanical property testing platform is the basis for obtaining cryogenic mechanical property data of materials. Therefore, based on the existing cryogenic mechanical testing platform of the team, a system-level design of the modified cryogenic mechanical testing platform was designed and implemented. The modified platform is named Mechanical Performance Testing Platform for Liquid Hydrogen Temperature Zone and it is using a Gifford-Mcmahon refrigerator to provide cryogenic cooling and a refrigerated helium circulation loop to transfer the cooling to the specimen effectively. The lowest test temperature can reach the liquid hydrogen temperature range 20K. Finally, tensile tests of S30408 (Equivalent to UNS S30400) austenitic stainless steel at 20K and 77K are carried out by the Testing Platform.