Formation mechanism and conditions of fine primary silicon being uniformly distributed on single αAl matrix in Al-Si alloys
| Autor: | Lei Zhang, Guo-wei Chang, Li Qingchun, Shu-ying Chen |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
Materials science
Silicon Alloy chemistry.chemical_element 02 engineering and technology Treatment parameters engineering.material 010402 general chemistry 01 natural sciences Matrix (geology) Solidification process Phase (matter) lcsh:TA401-492 General Materials Science Composite material Modification treatment Eutectic system Mechanical Engineering Al-Si alloy Cooling rate Melt stir 021001 nanoscience & nanotechnology Microstructure 0104 chemical sciences chemistry Mechanics of Materials engineering lcsh:Materials of engineering and construction. Mechanics of materials 0210 nano-technology |
| Zdroj: | Materials & Design, Vol 193, Iss, Pp 108853-(2020) |
| ISSN: | 0264-1275 |
| Popis: | In this study, solidification microstructure of fine primary silicon being uniformly distributed on single αAl matrix was obtained when adding Cu–9 wt%P alloy to an Al–10 wt%Si alloy melt or an Al–20 wt%Si alloy melt, stirring at 200 r/min for 12 min and cooling at the cooling rate of 16.3 K·s−1. The change law of silicon phase size with cooling rate and modified treatment parameters was determined by examining the solidification microstructures. It was found that ultrafine AlP was easily swallowed by primary silicon when the cooling rate was slow. The formation mechanism of superfine AlP particles, the growth process of αAl phase around primary silicon and the disappearance process of eutectic silicon were researched under intense stirring of the melt during the Cu–9 wt%P alloy modification. Moreover, the conditions under which fine primary silicon was uniformly distributed in single αAl matrix in hypereutectic Al-Si alloy were put forwarded. Finally, the formation mechanism of the solidification microstructure without eutectic Si in hypereutectic Al-Si alloy was analyzed. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect