泡沫Al-0.38Sc合金的力学性能和耐腐蚀性能

Compressive Strength and Corrosion Resistance Properties of Cellular Al-0.38Sc Foams

采用熔体发泡法制备孔隙率为48%~86%的闭孔泡沫Al-0.38Sc合金,研究Sc对闭孔泡沫铝力学性能、压缩形为和耐腐蚀性能的影响。结果表明,经适当热处理后,泡沫Al-0.38Sc合金基体中均匀析出大量纳米级Al3Sc粒子,这些粒子可有效钉扎晶界和位错,改善闭孔泡沫铝的压缩力学性能。热处理还可有效改善泡沫Al-0.38Sc合金的耐腐蚀性能,经热处理后的泡沫Al-0.38Sc试样自腐蚀电流与Nyqusit曲线半径与泡沫铝基本相当,这表明加入适量的Sc并配合适当热处理,可有效提高泡沫Al-0.38Sc合金的力学性能和耐腐蚀性能。

The cellular Al-0.38Sc foams with a porosity ranging from 48% to 86% were fabricated successfully via the melt-foaming method.The compressive behaviors,corrosion resistance and effects of minor Sc additions on the strengthening mechanism of the cellular Al-Sc alloy foams were investigated.The results reveal that minor Sc additions can improve dramatically the compressive strength of the cellular Al foams due to formation of the Al3Sc precipitates uniformly distributed in the matrix after heat treatment,to pin the grain boundary/dislocations.Moreover,the self-etch current and radius of the Nyqusit curve radius of the cellular Al-0.38Sc foams are close to cellular Al foam,showing that the Sc addition combined with proper heat treatment is an effective way to improve the mechanical performance of Al-based alloy foams with desirable corrosion resistance.