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.

Examples for refining the microstructure of metallic materials used for additive manufacturing are described herein. An example can involve generating a first layer of an integral object by heating a metallic material to a molten state such that the metallic material includes a solid-liquid interface. The example can further involve applying an electromagnetic field or vibrations to the metallic material of the first layer. In some instances, the electromagnetic fields or vibrations perturb the first layer of metallic material causing nucleation sites to form at the solid-liquid interface of the metallic material in the molten state. The example also includes generating a second layer coupled to the first layer of the integral object. Generating the second layer increases a number of nucleation sites at the solid-liquid interface of the metallic material in the molten state. Each nucleation site can grows a crystal at a spatially-random orientation.

Examples for refining the microstructure of metallic materials used for additive manufacturing are described herein. An example can involve generating a first layer of an integral object by heating a metallic material to a molten state such that the metallic material includes a solid-liquid interface. The example can further involve applying an electromagnetic field or vibrations to the metallic material of the first layer. In some instances, the electromagnetic fields or vibrations perturb the first layer of metallic material causing nucleation sites to form at the solid-liquid interface of the metallic material in the molten state. The example also includes generating a second layer coupled to the first layer of the integral object. Generating the second layer increases a number of nucleation sites at the solid-liquid interface of the metallic material in the molten state. Each nucleation site can grows a crystal at a spatially-random orientation.

A micro-nano incremental mechanical surface treatment method, comprising the following steps: using a modification tool having a designable end to contact a surface of a substrate material, rotating the modification tool in a local region and compressing the material surface, presetting processing parameters by means of 3D modeling software, and after the tool has processed the entire surface, enabling the tool to move downwards to the indented surface compressed previously. The process continues until the surface material is compressed to a pre-defined thickness, thereby achieving the goals of grain refinement and surface performance improvement. By means of the present method, a workpiece having a complex shape can be flexibly and designably surface modified. The method has the advantages of high bonding strength, no pollution, and low cost.

A method for surface treatment of a workpiece includes providing the workpiece with hardened workpiece surface, clamping the workpiece, removing material from the hardened workpiece surface with a material removal tool to produce a machined surface with first machining tracks, and rolling the machined surface with a rolling tool by overlapping the first machining tracks to produce a rolled surface with second machining tracks. A distance between the material removal tool and the rolling tool measured in an axial direction of the workpiece is varied in an oscillating manner. The material removal tool may be advanced in the axial direction at a constant speed and the rolling tool may be advanced in the axial direction at an oscillating speed, or the rolling tool may be advanced in the axial direction at a constant speed and the material removal tool may be advanced in the axial direction at an oscillating speed.

A method for processing an inner wall of a cylinder of an internal combustion engine includes providing a cylinder and processing an inner wall of the cylinder. The cylinder extends along a cylinder axis. The inner wall of the cylinder is processed in such a manner that at least one first structural region and one second structural region are formed along the cylinder axis. A geometry of the first structural region differs in design from a geometry of the second structural region.

Provided are a silver article formed using pure silver, which has high Vickers hardness and prohibits the occurrence of metal corrosion and the occurrence of discoloration; and its method. Disclosed are a silver article and its method, wherein the Vickers hardness is adjusted to 60 HV or higher, and when the height of the peak of 2θ=38°±0.2° by an XRD is designated as h1, and that of 2θ=44°±0.4° is designated as h2, h2/h1 is adjusted to 0.2 or greater.

Processing tool for processing a surface of a workpiece. The processing tool includes a tool body which defines a tool axis. At least one first roll element, which is borne by the tool body, is rotatable around a first roll element axis and has a first outer surface with a rough surface structure in at least one first working section configured for rolling contact with the workpiece surface. Further, at least one second roll element, which is borne by the tool body, is rotatable about a second roll element axis and has a second outer surface that, in at least one second working section configured for a rolling contact with the workpiece surface, has a distance (r2) to the tool axis, which is less than a distance (r1) of the at least one first working section to the tool axis.

Processing tool for processing a surface of a workpiece. The processing tool includes a tool body which defines a tool axis. At least one first roll element, which is borne by the tool body, is rotatable around a first roll element axis and has a first outer surface with a rough surface structure in at least one first working section configured for rolling contact with the workpiece surface. Further, at least one second roll element, which is borne by the tool body, is rotatable about a second roll element axis and has a second outer surface that, in at least one second working section configured for a rolling contact with the workpiece surface, has a distance (r2) to the tool axis, which is less than a distance (r1) of the at least one first working section to the tool axis.

A forming device and a method for forming an inner rim of an annular round blank. The forming device has a lower tool with a movable die and an upper tool arranged opposite the lower tool along a working axis A. By means of the die, the annular round blank is moved out of a transport plane T and into a forming position U towards the upper tool and into the interior of a holding sleeve. Subsequently, the inner rim is formed with the aid of a forming tool. After forming, the annular round blank is moved out of the forming position U and back into the transport plane T by means of the lower tool and/or the upper tool. The forming device and the forming method can occur while the round blanks are being fed to an embossing station while being transported by a revolving table.