Friction stir welding
Orbitalreibschweißen is a friction welding.
Method
In contrast to the closely related spin welding, the parts must not be rotationally symmetric here. The power supply is introduced by a relative movement of the parts to be joined, by means of a circular loop oscillating motion of both parties or one of the parts, similar orbital sander. The parts do not perform rotation from each other. The orientation of the axes thus remains the same. When Orbitalreibschweißen, 15620 concept called "single Orbitalreibschweißen " according to ISO, swings only one of the components; the " multi- Orbitalreibschweißen " both components. An orbital relative movement also occurs when both components rotate with an axis offset in the same direction.
Areas of application
The method is a new manufacturing technology for high-quality metal and plastic compounds and is used only for a few years in Germany in the field of automotive supply industry for serial parts. The biggest advantages of friction welding are the various material combinations. The Orbitalreibschweißen solves this on the restriction to rotationally symmetric parts and allows almost any part of cross-sections. As a possible joining geometries ribbon compounds, square hollow sections, extrusions, chassis parts, and other compounds on non-rotating parts are possible.
Possible material combinations:
- Steel with aluminum
- Aluminum with copper
- Brass with aluminum
- Aluminum with ceramic
- Titanium alloy, with titanium alloy
- Polyethylene with polyethylene
- Wood with wood
Limitations
In unfavorable component geometries, for example, in poor Spannbarkeit of parts and high parts by weight and in thin-walled sections, but also in non- matching materials, the process limit is reached.
In friction welding, usually produces a weld by the displaced material during pressing. A removal of the weld bead by twisting by means of a turning tool in the machine is not easily possible due to the orbital motion control of the components. It should be aimed through a die in an automated unclamping.
Machine
The machines used are similar to Rotationsreibschweißmaschinen. A rotating movement is transmitted via the so-called orbital eccentric disk. Clamping there summarizes the parts to be joined. In an enclosure which prevents the penetration blasted off parts, as is necessary in Rotationsreibschweißmaschinen, can be dispensed with, since acceleration of loose parts due to the usually small amplitudes of about 1.5 mm is not critical. Mitigation measures are recommended. The structure is compared to Linearreibschweißmaschinen, which likewise do not have any restriction in rotationally symmetrical parts, is considerably smaller and simpler. This has a significant impact on the cost. In recent years, production-ready machines were developed in which the machine building and machine control is optimized to simple inputs on the control panel an orbital, multi -orbital and a linear relative motion of the joining partners is possible.