Deformation induced grain boundary segregation in nanolaminated Al–Cu alloy
| Autor: | Wenbo Xu, Xiaochun Liu, Kathy Lu, Xixia Li |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
010302 applied physics
Nanostructure Materials science Polymers and Plastics Alloy Metals and Alloys 02 engineering and technology engineering.material Liquid nitrogen 021001 nanoscience & nanotechnology 01 natural sciences Electronic Optical and Magnetic Materials Grinding Lattice (order) 0103 physical sciences Ceramics and Composites engineering Grain boundary Surface layer Deformation (engineering) Composite material 0210 nano-technology |
| Zdroj: | Acta Materialia. 182:207-214 |
| ISSN: | 1359-6454 |
| DOI: | 10.1016/j.actamat.2019.10.036 |
| Popis: | A gradient nanostructured surface layer was formed in an Al–4 wt%Cu alloy processed by means of surface mechanical grinding treatment at liquid nitrogen temperature. Within the deformed surface layer, laminated structures with a wide range of thickness were formed. With a decreasing depth from the treated surface, lamellae thickness decreases accompanied by an increased fraction of high angle grain boundaries (HAGBs) from 10% to 70%. In the topmost surface layer, nanolaminated (NL) structures were found with an average thickness as small as 28 nm and a HAGB fraction of 70%. Composition analysis indicated that Cu atoms segregate at NL boundaries in the as-prepared sample, Cu concentration is about 3–4 times higher than that in the lattice. The obvious grain boundary (GB) segregation of Cu induced by cryogenic plastic deformation is attributed dynamic interaction between solute atoms with gliding dislocations. GB segregation of Cu is responsible for the stabilization of the NL structures with a much finer structural size than that in pure Al, resulting in higher hardness. The deformation-induced GB segregation provides an alternative strategy to achieving stable high strength nanostructures in Al alloys. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect