Patent attributes
A method for relieving residual stress in an object includes: (a) applying a vibration energy to the object over a frequency range; (b) monitoring vibration behavior of the object over the frequency range so as to identify a reference frequency, where the vibration amplitude of a fundamental wave component of the wave pattern is approximately one third of a maximum vibration amplitude of a resonate frequency of the object, and an optimum frequency, where the frequency and the vibration amplitude of the harmonic wave component of the wave pattern are respectively larger than those of the harmonic wave component of the wave pattern of the reference frequency; and (c) applying the vibration energy to the object at the identified optimum frequency for an extended period of time.