Solidification microstructure in a supercooled binary alloy

• Autorzy: Wang, Hongfu , Tang, Cheng , An, Hongen , Zhao, Yuhong
• Języki publikacji: EN

Abstrakty

EN

The maximum undercooling that has been achieved for Ni-Cu alloy, by using molten glass purification and cyclic super-heating technology, is 270 K. With the help of high-speed photography, the solidification front images of Ni-Cu alloy at various typical undercooling were obtained. Two grain refinements occurred in the range of 60 K< ΔT < 100 K and ΔT > 170 K, the solidification front became smoother, and the solidification position appeared randomly. With the increase of undercooling, the transition from solute diffusion to thermal diffusion leads to the transition from coarse dendrite to directional fine dendrite. At large undercooling, considerable stress is accumulated and some dislocations exist in the microstructure. However, the proportion of high-angle grain boundaries is as high as 89%, with twin boundaries of 13.6% and most strain-free structures, and the microhardness decreases sharply. This indicates that the accumulated stress at large undercooling causes the plastic strains in the microstructure, and in the later stage of recalescence, part of the plastic strains is dissipated by the system and acts as the driving force to promote the recrystallization of the microstructure.

Słowa kluczowe

EN

alloy; microstructure; rapid solidification; crystal growth

• Czasopismo: Materials Science Poland
• Rocznik: 2021
• Tom: Vol. 39, No. 3
• Strony: 383--394
• Opis fizyczny: Bibliogr. 19 poz., rys.

Twórcy

autor

Wang, Hongfu

• School of Mechanical Engineering, North University of China, Taiyuan, Shanxi 030051, China,

autor

Tang, Cheng

• School of Mechanical Engineering, North University of China, Taiyuan, Shanxi 030051, China

autor

An, Hongen

• Faculty of Engineering, University Malaysia Sabah, Kota Kinabalu 88400, Malaysia

autor

Zhao, Yuhong

• College of Materials Science and Engineering, North University of China, Taiyuan, Shanxi 030051, China,

Bibliografia

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Identyfikatory

DOI

10.2478/msp-2021-0031