The invention concerns an engraved surface of a deformation tool which deforms a workpiece with an active medium, wherein the deformation tool has a pressure agent feed for the active medium and an engraved surface according to the desired final contour of the workpiece. Accordingly deformation methods are performed with hydro-deforming as well as of internal high-pressure metal forming of a wall of a workpiece by the engraved surface of the tool by way of the pressure medium. Upon withdrawal of the workpiece the pressure medium can pass to the engraved surface of the tool, during the deformation of the following workpiece no contact between the engraved surface and the workpiece wall occurs due to the pressure agent adhering to the engraved surface, whereby undesired deformations occur on the workpiece. Accordingly to overcome this problem microstructures are provided on the engraved surface, wherein the microstructures are suitable to receive the active medium adhering to in the wall of the workpiece and the engraved surface. Undesired deformations of the workpiece are thereby avoided. Furthermore the engravings can serve as a depot for lubricant and thus to minimize friction.