Non-equilibrium effects on solid transition of solidification microstructure of deeply undercooled alloys

ABSTRACT

Integrated effects of undercooling and solute drag on recrystallisation mechanism of rapid solidification microstructure were investigated in highly undercooled Ni-Cu alloys. The equiaxed grained microstructures were prepared by fluxing method and subsequent quenching. Annealing the microstructures of the as-quenched alloys, substantial recrystallisation growth was observed. Applying solute trapping model of undercooled melt and solute drag model of solid-state transformation, it can be inferred that the microstructural evolution was dominated by nucleation and growth of recrystallisation process which is strongly dependent on the initial undercooling of the alloy melt and the solute drag force of the solid-state transition process.

KEYWORDS:

• Solidification
• crystal growth
• metals and alloys
• defects
• recrystallisation

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work is supported by International Cooperation project of the Ministry of Science and Technology of China (No. 2014DFA50320), the National Natural Science Foundation of China (Nos. 51674226, 51574207, 51574206, 51274175), International Science and Technology Cooperation Project of Shanxi Province (Nos. 2015081041), research project supported by Shanxi Scholarship Council of China (Nos. 2016-Key 2). The authors are grateful to the financial support of National Basic Research Program of China (973Program, 2011CB610403).