AEROSPACE APPLICATIONS

The need for EBW as a critical fabrication process in realising elements and assemblies for spacecraft and launch vehicle programmes due to the following unique requirements.

1. Welded joints appear in the most critical sections and the performance of the elements / systems depends upon the quality and reliability of these joints.
2. Requirements of high quality leak proof welded joints for space craft propulsion system with long mission lives under extreme space environment.
3. Elimination of catastrophic failures in case of launch vehicle propellant tankage assemblies with common bulk head configuration.
4. Requirement for achieving high quality welds in case of spacecraft thrusters and engines involving materials like Ti, Cb, etc
5. Distortion free joining for realising thin walled Ti alloy propellant tankage assemblies for spacecraft involving upto 75 EBW joints in a single tankage assembly.
6. Requirements of achieving high quality joining of thick sections of titanium alloy hemisphere for high pressure helium gas bottles.

Titanium forgings have been joined by EBW t o form a rot or hub of 3000 mm in diameter for a new helicopter. The Ti - 6 AI - 4 V alloy parts of 55 mm and 255 mm thick are EB welded in one pass and joined in the areas of the hub. The hub and blade of the helicopter were formed by EBW since hub and blades could not be forged in one piece. EB welding is being extensively used to join Inconel 718 components together on the engines for the space shuttle.