Ie. Boitsov et al., Physical and mechanical characteristics of EP741 and EP99 high-temperaturenickel alloys in high-pressure hydrogen gas, INT J HYD E, 24(9), 1999, pp. 919-926
This paper presents research of the hydrogen gas effects on physical and me
chanical properties of the precipitation-hardened nickel alloys EP741 and E
P99 at pressures up to 65 MPa and temperatures up to 840 degrees C. It has
been shown that conventional yield strength, tubular-shaped sample fracture
stress and long-term strength are not practically affected by hydrogen. Th
e characteristics of alloy ductility are more susceptible to hydrogen effec
t. EP741 alloy Is especially susceptible to the hydrogen environment effect
at temperature of 460 degrees C, and EP99-at temperatures of 20 degrees C
and 460 degrees C. Hydrogen permeability relationships for alloys in a wide
range of temperature and pressure were obtained. (C) 1999 International As
sociation for Hydrogen Energy. Published by Elsevier Science Ltd. All right
s reserved.