Influence of Environmental Temperature on the Fatigue Strength of VH3 Compressed-Hydrogen Tanks

Abstract

We investigated a temperature influence on the fatigue life of VH3 compressed-hydrogen tanks. We conducted pressure-cycle tests under the extreme-temperature conditions. As a result, the lifetime of the VH3 tank became short under low-temperature condition and became long under high-temperature condition. The VH3 tank is subjected to autofrettage for improving fatigue strength, in which compressive stress remains in the liner and tensile stress in the CFRP layer. This survey revealed that the effect of autofrettage changes when an environmental temperature changes by the difference of the coefficient of thermal expansion of CFRP and the aluminum alloy.