An ultra-strong and ductile crystalline-amorphous nanostructured surface layer on TiZrHfTaNb0.2 high-entropy alloy by laser surface processing

Luo，Jiasi1,2; Sun，Wanting1; Liang，Dingshan2; Yang，Wenqing1; Chan，K. C.1; Ren，Fuzeng2; Yang，Xu Sheng1,3

2023-03-01

10.1016/j.matdes.2023.111710

Materials and Design   Impact Factor & Quartile

0264-1275

1873-4197

Heterogeneous crystalline-amorphous nanostructures have been documented to show superior strength-ductility synergy via the co-deformation cooperative effects of nanograins and amorphous grain boundaries. In this work, a facile laser surface remelting technique with rapid cooling rate was successfully developed to fabricate a ∼ 100 μm-thick gradient nanostructured layer accompanied by phase decomposition on a TiZrHfTaNb high-entropy alloy, where a ∼ 5 μm-thick crystalline-amorphous nanostructured top surface layer with an average grain size of ∼ 7 nm was obtained. Such crystalline-amorphous nanostructured layer shows an ultrahigh yield strength of ∼ 6.0 GPa and a compression strain of ∼ 25 % during the localized micro-pillar compression tests. The atomic observations reveal that co-deformation cooperative mechanisms include the well-retained dislocation activities in nanograins but crystallization in amorphous grain boundaries, which subsequently lead to the grain coarsening via grain boundary-mediated plasticity. This study sheds light on the development of high-performance high-entropy alloys with novel crystalline-amorphous nanostructures and provides significant insight into their plastic deformation mechanisms.

Crystalline-amorphous nanostructure Hetero-nanostructure High-entropy alloy Laser surface remelting Micro-pillar compression tests

English

Corresponding

2-s2.0-85147841914

Scopus

1.Department of Industrial and Systems Engineering,Research Institute for Advanced Manufacturing,The Hong Kong Polytechnic University,Kowloon,Hung Hom,Hong Kong
2.Department of Materials Science and Engineering,Southern University of Science and Technology,Shenzhen,518055,China
3.The Hong Kong Polytechnic University Shenzhen Research Institute,Shenzhen,518060,China

Luo，Jiasi,Sun，Wanting,Liang，Dingshan,et al. An ultra-strong and ductile crystalline-amorphous nanostructured surface layer on TiZrHfTaNb0.2 high-entropy alloy by laser surface processing[J]. Materials and Design,2023,227.

Luo，Jiasi.,Sun，Wanting.,Liang，Dingshan.,Yang，Wenqing.,Chan，K. C..,...&Yang，Xu Sheng.(2023).An ultra-strong and ductile crystalline-amorphous nanostructured surface layer on TiZrHfTaNb0.2 high-entropy alloy by laser surface processing.Materials and Design,227.

Luo，Jiasi,et al."An ultra-strong and ductile crystalline-amorphous nanostructured surface layer on TiZrHfTaNb0.2 high-entropy alloy by laser surface processing".Materials and Design 227(2023).