Special Techniques is well equipped with two electron beam welding systems.
Two 3kW 60kV devices are available, incorporating CNC XY tables, rotary chucks and beam pattern generators. The vacuum chambers can accommodate workpieces of ~300mm maximum length, ideal for prototype development.
Electron beam welding offers many advantages over conventional welding:
- Minimal distortion;
- Low heat input;
- Reduced heat affected zone;
- Oxide free;
- Excellent homogeneity of weld zone;
- Suitable for very thin material sections.
The cylinder shown bottom left was produced for a European Space Agency probe, designed to land on and analyse the material of a comet. The unit was designed to carry hydrogen for use with a mass spectrometer device.
The technique was selected to ensure maximum uniformity and strength of joint. Subsequent destructive test results indicated a factor of safety of 12, three times the predicted failure pressure in rupture mode.
Electron beam welding is suitable for joining a large number of metallic media, that conventional welding would be unsuitable for.
Vanadium, titanium, aluminium, stainless steel, inconel, kovar, platinum, nickel, tantalum, rhodium, molybdenum and nimonic list amongst the materials welded at Special Techniques.
Different combinations of materials may also be welded. As shown below (middle and right), ultra thin deep-drawn vanadium cells have been welded to commercially pure titanium.