VIBRATION STRESS RELIEF... WHAT IS IT?

In the field of mechanical treatments aimed at reducing the internal stresses of a material through cyclical mechanical stress, we find the Vibration Stress Relief method (commonly known as the "VSR method" or "vibration stress relief treatment").

Using mechanical vibrations induced by a motorized eccentric mass, an oscillatory regime is generated in the component. These oscillations, interacting with the pre-existing residual stress within the component, produce deformations that exceed the plastic deformation threshold, thereby establishing a new stress-free equilibrium within the component.

Vibration stress relief is a low-cost, optimized alternative to thermal treatments (e.g., furnace annealing).

The Vibration Stress Relief (VSR) method achieves similar results to those obtained with thermal treatments but offers several fundamental advantages:

1. It prevents deterioration of mechanical properties and avoids grain modification, typical consequences of thermal treatments.
2. There is no need to transport the component to be relieved: vibration stress relief equipment is compact enough to allow on-site treatment of components.
3. Minimal execution times (treatment time per component rarely exceeds 2-3 hours).
4. The component’s surfaces are not contaminated by residues.
5. The material's metallurgical characteristics remain unchanged.
6. The treatment effects can be focused on critical areas of the component.
7. It eliminates dependence on facilities and equipment (e.g., annealing furnaces).

Basic Principle of Vibration Stress Relief Treatment

In industrial terms, when an eccentric mass is applied to a component, it induces an oscillatory regime within the component that depends on:

1. The geometric characteristics of the component,
   b. The positioning of the eccentric mass,
   c. Oscillation frequencies,
   d. The kinetic energy applied to the eccentric mass,
   e. The constraints imposed on the component.

Effectively performing vibration stress relief means knowing how to position the eccentric mass (the excitation source) and determine the optimal oscillation frequencies and proper working parameters to direct the maximum energy from the vibrator precisely where it is needed.

Does Vibration Stress Relief work? Yes!

The results of a well-executed vibration stress relief treatment are comparable to those achieved through thermal treatments. It is possible to nearly eliminate residual stresses, which significantly extends the fatigue life of the component. Components subjected to vibration stress relief often demonstrate twice the service life of similar untreated components.