摘要
研究了时效热处理和RRA热处理对国产7050铝合金强度、韧性及抗应力腐蚀性能的影响。结果表明:合金经 140℃,24h 处理,强度和抗应力腐蚀性能优于传统的 T6处理;RRA 处理可使合金强度达到峰值,而抗应力腐蚀性能达到双级时效水平。分析了断裂韧性的影响因素,指出国产7050铝合金具有良好断裂韧性的原因是Fe,Si 杂质含量少,Mg,Cu 含量偏低。
As a domestic material, the aluminium alloy 7050 was investigated forthe effects of aging treatment and RRA-(retrogression and reaging) treatmenton its strength, toughness and SCR (stress corrosion resistance). The resultsshow that both the strength and SCR of 7050 alloy are higher than those bythe conventional T6 treatment if the alloy was aged at 140℃ for 24hr, and thatRRA enable the strength to be increased up to a peak value with SCR up toa condition as double aging. It is found that the good fracture toughness of7050 alloy is contributed by the less Fe and Si impurities and lower Mg and Cucontents.
