Determination of residual stresses by ESPI-HD method

We have an equipment and technology for determination of residual stresses. They are based on the hole-drilling method and electron speckle
interferometry (ESPI-HD method).

The application of electron speckle-interferometry unlike strain measurements with gages allows receiving bigger amount of displacement data around drilled holes without averaging. The method has all advantages of conventional hole drilling method (standard ASTM E837 ) but gives additional possibility to get an extra information about distribution of RS. For example, it is possible to make measurements on a weld reinforcement and we don't need to remove it (removing can cause redistribution of stresses) or it is possible to use experimental data only from one side of the area around a drilled hole (it is convenient for measurements near edges, stiffeners) and so on.

We've extended application of the ESPI-HD method for determination of RS in a specific conditions such as presence of surface curvature (tubes of a small diameter), small object thickness (from 2 mm) and others.

At the moment I am interested in the development of our method for the determination of residual stresses in orthotropic materials (composite materials, etc).

If you are interested in the determination of residual stresses in your samples, we could collaborate and conduct a joint scientific research.