Vibration stress relief of superalloy components
A method of conditioning and stress relief for superalloy components includes vibrating the component during welding at a subharmonic frequency. The proper frequency is selected to be below a harmonic frequency, and to produce an amplitude in the range of ⅓ to ½ the amplitude produced by a harmonic frequency. The component to be repaired is vibrated during and after welding at this frequency.
1 . A method of reducing stresses within a superalloy substrate during welding, the method comprising:
identifying a harmonic frequency of the substrate;
selecting a frequency that produces an amplitude of about ⅓ to ½ an amplitude produced by the harmonic frequency, and which is a lower frequency than the harmonic frequency;
vibrating the substrate at the selected frequency while welding the substrate.
2 . The method according to claim 1 , further comprising vibrating the substrate at the selected frequency as the substrate cools after welding.
3 . The method according to claim 1 , further comprising vibrating the substrate with a force having a ratio to substrate weight of about 9:1 to about 16:1.
4 . The method according to claim 1 , wherein the frequency selected is between about 0 Hz. and about 120 Hz.
5 . The method according to claim 1 , further comprising:
testing various frequencies beginning with a lower frequency and progressing towards higher frequencies;
identifying the second harmonic frequency encountered during testing; and
selecting a frequency that produces an amplitude of about ⅓ to ½ an amplitude produced by the second harmonic frequency, and which is a lower frequency than the second harmonic frequency.
6 . The method according to claim 5 , further comprising vibrating the substrate at the selected frequency as the substrate cools after welding.
7 . The method according to claim 5 , further comprising vibrating the substrate with a force having a ratio to substrate weight of about 9:1 to about 16:1.
8 . The method according to claim 5 , wherein the frequency selected is between about 0 Hz. and about 120 Hz.