Abstract: A method of preparing a surface of a workpiece of solid ductile material to provide a transition zone between that material and a different material to be brought into intimate contact with the first material, involves relatively moving the workpiece surface and a substrate to which are bonded adhesive particles much harder than the ductile material through a contact zone while pressing the particles of abrasive into the material surface, such that the abrasive particles score recesses extending longitudinally of the material surface while displacing said ductile material from the scores to form processes integral with the material and extending outwardly from the surface and parallel to the second recesses into spaces between the material surface and the substrate, the recesses and processes together providing at the prepared surface a transition zone between the ductile material and the different material.