Laser sintering of polyamides and other polymers

With the evolution of additive techniques from prototyping tools (Rapid Prototyping; RP) to the production of actual end-use parts (Additive Manufacturing; AM), there is a growing need to develop and be able to process a much greater variety of materials than is currently possible. The handful of current polymeric materials that exist for processing by additive techniques does not meet the requirements of the majority of commercial products. There is therefore considerable interest from industrial and academic organisations, who realise the capabilities this technology has in the design and implementation of products, to increase material choice and to have a comprehensive understanding of the fundamental material properties. This review paper looks at the factors that need to be considered when selecting and processing polymers and the research that has been carried out to date, focussing on laser sintering, which is one of the most established and widely used Additive Manufacturing approaches. It also examines the limitations of current laser sintering systems in relation to the processing of polymer materials. The effect this has on the development of new and improved materials for laser sintering is evaluated, in addition to the difficulties experienced in maintaining consistency with current laser sintering polymers.