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Highly oriented carbon tapes have been produced from mesophase pitch with thickness 10 micon to 20 micron and width of ca. 1 mm. The tapes show thickness shrinkage of 36% but only small width reductions of around 2% upon carbonisation. Increasing the heat treatment temperature resulted in an increase in the apparent density of the tapes. X-ray texture analysis for the transverse area of tape heat treated to 1600 deg C indicate that the predominant molecular arrangement is parallel to the tapes main surface although there is evidence of some tilting of the molecular planes in relation to the surface of the tape. The tapes were highly flexible after carbonisation at 1000 deg C despite the fact that their transverse areas were comparable to that of ca. 150 conventional carbon fibres. The strength and Young modulus of these tapes compare favourably with those of commercial high performance carbon fibres of much lower transverse cross-sectional area. Continuous springs with diameters as low as 1 mm to 2 mm were successfully formed from the carbon tapes. The potential of these carbon springs to act as biocompatible endovascular supports (or stents) is currently being investigated with respect to their introduction and deployment and their in-situ behaviour within coronary arteries. As part of this study, the mechanical properties of the carbonised springs have been investigated. Following carbonisation to 1000 deg C, the springs were highly extensible and flexible with elastic extension to > 2000%, in the case of 10 mm diameter springs. Longitudinal spring stiffness measurements show hardening and softening behaviour upon extension for 0.70 mm and 0.32 mm-wide springs, respectively. Springs of 0.70 mm wide tape show a radial compressibility of over 40% (reduction in diameter) and a radial strength of 0.04 N/mm. These springs also remain intact upon twisting through more than 1000 degree of angle in both clockwise and anticlockwise directions. The successful forming of springs and their subsequent mechanical performance can be greatly affected by the presence of various defects in the tape, as observed in SEM studies.