Hydro-Cavitation Blasting
A high-energy water jet process utilizing intentionally imploding vapor bubbles for material removal and surface densification. This reduces the thermal and mechanical baseline load on the component.
In hydro-cavitation blasting, vapor bubbles in the water jet collapse and create tiny pressure surges. This removes material and compacts the surface, similar to shot blasting, but with water. The advantage for welding is that the workpiece is hardly thermally stressed. So you get less distortion and no cracks from thermal stresses. But if you set the pressure too high or stay in one place too long, you'll eat into the surface. Set the pressure so that you just barely remove the scale or oxide layer, but don't attack the base material. Keep the distance constant and move evenly over it. Clean water is a must, otherwise you'll just embed dirt into the surface and risk corrosion.