Connect, no.140, January - February 2006, p.2

Timber welding - not such a tall tale

Specimens of oak and beech joined by the linear friction welding process

The world of furniture manufacture could be turned on its head shortly if a well established joining process, usually associated with joining steel, titanium, aluminium and thermoplastics, proves viable for welding wood.

Already linear friction welding of oak and beech specimens have been joined at TWI using its Bielomatik vibration welding kit. And mechanical tests on completed joints have thrown up impressive joint performance data.

'It sounds incredible but true ... there are still more questions than answers' project leader Scott Andrews told Connect. 'By vibrating two planed specimens at a pre-determined frequency, under a specific compressive load, for a specific cycle time, we are able to join them together. We believe a matrix of cells, mainly lignin, is melting and interlocking at the joint line ... and then forming a bond during solidification'.

In the same way that TWI's invention of friction stir welding has overturned the use of rivets in aircraft manufacture, so linear friction welding of timber could radically disrupt the traditional use of fasteners and adhesives in furniture manufacture.

'The research is in its embryo stage right now' comments Andrews, 'for the future we're looking at starting a Group Sponsored Project.'

For more information, contact Scott Andrews. E-mail: scott.andrews@twi.co.uk Copyright © 2006 TWI Ltd