论文信息 - In-situ heating observations on superlattice dislocation in Ni{sub 3}(Al,Zr) single crystals

In-situ heating observations on superlattice dislocation in Ni{sub 3}(Al,Zr) single crystals

The TEM weak-beam technique has been used to investigate the behavior of dissociated superlattice dislocation in Ni{sub 3}Al single crystal as a function of temperature. The observed dislocation with the Burgers vector of [{bar 1}10] partly dissociated on the (001) plane forming Kear-Wilsdorf (KW) lock. The dissociated pair did not indicate significant variation of separation in the temperature range from room temperature to 773K but turned to form a jog at 773K. At 898K, which is near the peak temperature, the dissociated segment constricted completely. The experimental observations are discussed.

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