A method for the autofrettage of a workpiece may involve arranging the workpiece between a first securing means and a second securing means, and applying high-pressure fluid to an internal volume of the workpiece that is formed between the first and second securing means. A die or ram may be driven into the internal volume through an inlet in the first securing means. Consequently, as a result of the ram being advanced, not only is a fluid pressure generated in the internal volume, but also the workpiece is mechanically autofrettaged by way of the ram. A device may be employed to perform such hydromechanical autofrettage of the workpiece.