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Composite materials containing thin Shape Memory Alloy (SMA) wires show great promise as materials able to adapt their shape, thermal behaviour or vibrational properties during service. Tools for designing such materials are however far from being available. The work presented here reports the main achievements of a concerted European effort towards the establishment of a fundamental understanding for manufacturing and design of SMA composites. The following major steps are examined: selection and characterisation of the material constituents, development of manufacturing processes for the production of composites with pre-strained SMA wires, analysis and modelling of the action of the SMA wires in the composite, the contribution of the SMA-resin interface, analysis and modelling of the functional, thermomechanical, impact and durability properties of SMA composites and the development of a simple, large-scale, aerodynamic model. It is argued that the achievements of this research have brought the knowledge on SMA composites to a substantially higher level enabling reliable manufacturing and design, and the emergence of new industrial applications.

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The influence of annealing parameters on the martensitic phase transformation in sputter-deposited Ti rich Ni-Ti films is systematically studied by differential scanning calorimetry and by transmission electron microscopy. The annealing temperature range extends from the crystallization temperature of the films up to 900 • C. For increasing temperature, multiple phase transformations, transformations via an R-phase or direct martensite/austenite transformations are observed. A similar behavior is found for increasing annealing time. Related changes of the film microstructure, such as the strongly varying distribution of round Ti 2 Ni precipitates in the grains, are analyzed. Transformation temperatures could be shifted over a wide range by adjusting the film composition from 48 to 54 at.% Ti. The corresponding transformation curves, grain structure as well as nature and amount of precipitates were investigated. No subsequent annealing process is required for films deposited on substrates heated above about 500 • C. In this case, the as-deposited films have a very fine-grained and homogeneous microstructure.