Blown bulb

Ideally, incandescent light bulbs last for 42 days in continuous operation. But in reality, some do not burn out for years, while others last only a few days.

Fine cracks in the tungsten filament, which eventually cause it to break, are one reason that manufacturers are unable to produce a more uniform quality product  - a problem faced by both Osram and Philips, the world’s biggest light bulb manufacturers.

So far, the industry has relied on trial and error to improve the drawing process for the filament. But those production processes can be enhanced by simulating the behaviour of the filament material on a computer.

And supported by researchers from the Fraunhofer Institute for Mechanics of Materials IWM, that’s just what the manufacturers are doing – they are investigating the cracks and the resultant difficulties when spiralling the wire.

Osram project manager Bernd Eberhard is confident that,  “once we have more insight into the composition and behaviour of the filament, we will be able to optimise and standardise our production processes.”