Metallurgist, General Electric Company, Erie, Pa.
Pages: 11 Published: Jan 1973
The iron-nickel-base superalloy A-286 and its improved version, intermediate-aged V-57, were examined in bend fatigue at 950 to 1100 F (510 to 593 C) to determine whether using V-57 would be advantageous in low-frequency applications. The superiority might be expected because the latter is better in stress rupture than A-286. Nonreversed bending was done at frequencies close to 0.1 and 1 cpm, with a few tests at 10 cpm. The transition fatigue life, where the elastic and plastic strain ranges are equal, is below 500 cycles. Since most purely cyclic applications will involve much longer lives, the fatigue component of damage in these applications will be in the high-cycle fatigue regime. The data, which show V-57 to be superior to A-286 at 950 to 1100 F (510 to 593 C), also indicate that test frequencies should be chosen carefully to obtain meaningful data. There are several indications that the specimens can undergo further aging during testing and that their fatigue behavior is affected by the aging.
fatigue (materials), creep rupture strength, fatigue tests, bend tests, superalloys, high temperature test, nickel containing alloys, iron containing alloys
Paper ID: STP38861S