| Popis: |
The effects of Si, Fe and Zr elements on the high temperature properties and microstructure of ultrathin 3003mod aluminum alloy fins were studied by means of high-temperature tensile tests, sagging tests and microstructure analyses. The results show that the alloying of Si, Fe, and Zr elements formed a large amount of nano-scale α-Al(Mn,Fe) Si and Al3Zr particles, and significantly reduced the number of micro-scale coarse Al6(Mn,Fe) particles in the 3003mod aluminum alloy, exhibiting 5 to 10 MPa higher strength and better sagging resistance than 3003 aluminum alloy at the same temperature. The variations in properties such as high-temperature mechanical properties, sagging resistance and elongation below 400 °C were ascribed to the high-stability nanoparticles effectively preventing recovery and grain boundary migration, as well as reducing the nucleation cores of recrystallization. The nanoparticles in 3003mod aluminum alloy were coarsened significantly at 500 °C, and the grains were completely recrystallized and coarsened, resulted in a significant decrease in strength, sagging resistance and elongation compared with these at 400 °C. |
