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To investigate microstructural evolution and plastic deformation under tension, the rapid solidification processes of the Ni47Co53 alloy are first simulated by molecular dynamics methods at cooling rates of 1011, 1012 and 1013 K s−1. Then, the uniaxial tension simulation study was conducted on a single crystal, polycrystal and metallic glass, which were formed during the rapid solidification. The results show that the dislocation loops evolution in the crystal is caused by the slips and proliferation of stacking faults, and in terms of plastic deformation, the single crystal is carried by stacking faults, while a polycrystal is carried by grain boundaries. A metallic glass formed at the critical cooling rate and crystallized under tension, the plastic deformation is carried by grain boundaries and stacking faults in metallic glass. Ultimately, the stacking faults are the most resistant to plastic deformation. This study has great significance for the study of the mechanical properties of single crystals, polycrystals and metallic glass. [ABSTRACT FROM AUTHOR]

A molecular dynamics simulation has been conducted in Ni73Co27 and Ni74Co26 alloys during rapid solidification at the cooling rate of 1 × 1012 K/s. It indicates that two phase transitions occur with twice drops, and the number of FCC increases suddenly in Ni73Co27 alloy. And finally, FCC atoms are dominant with the amount of 92.94% at 300 K, which neatly arranges themselves into the crystalline structure. A lot of topologically close-packed clusters are formed in Ni74Co26 alloy, indicating the formation of metallic glass. The differences between the formations in crystalline hexagon and amorphous pentagon are demonstrated by three-dimensional visualization. [ABSTRACT FROM AUTHOR]