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Superplastic Forming and Diffusion Bonding (SPF/DB) has permitted the manufacture of some of the lightest, strongest, corrosion resistant, complex, and yet often elegant structures ever to be produced. For the last 30 years, all such components have been made by some form of high thermal-mass, isothermal method of production using conventional equipment, such as hot platen presses or furnaces.However, if laser(s) could be used just to heat the material to be superplastically formed, this could provide a novel, low thermal-mass, means of production which could, relatively easily, be integrated into a laser based manufacturing centre.In this paper, a concept is described of how a laser based manufacturing centre, comprised of a number of individual process cells, together with integrated pre and post SPF/DB operations, would work and the benefits that would result.The concept is based on four considerations. Firstly, that it is essential to heat the material directly and quickly. Secondly, the environment must be completely inert so that there is no contamination of components. Thirdly, the complete process of diffusion bonding must only entail the use of laser(s). Lastly, established laser activities such as cutting, welding, hole drilling or trepanning and the removal of surplus material, must be integrated into the process. In addition, the envisaged cells need to be modular in concept so industry can acquire capital plant progressively, thereby spreading the cost over time.

Superplastic forming (SPF) has traditionally relied on hot platen presses and furnaces as the principal heat sources to raise materials to superplastic forming temperatures. However, recent research, in the UK and the US, has concluded that such indirect heating methods are slow, expensive, and can only provide a single temperature to the work piece, which can be undesirable. In contrast, LISTechnology Limited (laser induced superplasticity technology) has been created to provide an alternative technology that can directly heat materials to be superplastically formed fast, at low cost and with the potential to control thickness distribution during forming through differential heating. The first ‘laser cell’ for components formed from single sheet titanium is currently being built to demonstrate how direct heating of SPF materials with a laser will significantly increase material heat up rates, compared with current methods, whilst the low thermal mass of the cell will allow rapid cooling to below oxidation temperatures, thus significantly reducing manufacturing cycle times. Furthermore, the cell will only utilise thermally stable, inert ceramic dies within which the titanium will be formed, these being contained within a sealed argon environment, thereby offering the possibility of alpha case free, rapid forming at high temperatures.

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