Microstructure of a Damascene sabre after annealing

X-ray phase analysis combined with high-resolution electron microscopy of samples taken from a genuine Damascus sabre after annealing for 24 h at 400 degrees C and 800 degrees C followed by slow cooling down to room temperature has led to a better insight into the nature of cementite nanowires, which have been discovered recently. According to the present study, nanowires remained after 400 degrees C annealing, but disappeared after heat treatment at 800 degrees C and subsequent cooling down. On the other hand, perlitic cementite has been retained qualitatively after the same treatment. Knowing that the exceptional mechanical properties of Damascene blades disappear after annealing, the present results suggest a significant influence of the nanowires upon these features.