Page 31 - Fiber Fracture
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16 ry "rn K.K. Chawla
Fig. 9. Bamboo-like grain structure of an AKS tungsten filament TEM
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Fig. 10. Bubbles in a tungsten filament. TEM (courtesy of B. Bewlay). The objective is to have a high
density of such tiny bubbles so that they pin the grain boundaries effectively against sliding, thus resulting
in a microstructure that is stable at the operating temperature.
