The alloy （AI-Cu-Mg） alloy important one dating back to the series （2xxx） where copper foundries basic element which represents the number （2）, the study relied on foundries add elements boron （B） and titanium...The alloy （AI-Cu-Mg） alloy important one dating back to the series （2xxx） where copper foundries basic element which represents the number （2）, the study relied on foundries add elements boron （B） and titanium （Ti） and then use a heat treatment （homogenizing process） to improve the corrosion resistance in saline （NaC1 3.5%） of the base alloy （A1-Cu-Mg）, was prepared four types of alloys （A, B, C, D） depending on the chemical composition. The results showed that the corrosion resistance in saline solution was the best resistance in the alloy （D） （A1-2% Cu-2% Mg-0.1% B-1.0% Ti） compared with the rest of bullion when an examination of corrosion of the alloy prepared after homogenizing. But by examining the surface roughness of the alloy ingot turned out that （D） is softer than the rest of the surface alloys and this is due to the addition of boron and titanium together increases surface smoothness in alloys because it works to reduce the grain size.展开更多
The evolution of microstructure parameters （precipitate size and volume fraction） for two types of Al-Zn-Mg-Cu alloys （7075 and 7055） during aging has been studied by synchrotron-radiation small angle X-ray scatte...The evolution of microstructure parameters （precipitate size and volume fraction） for two types of Al-Zn-Mg-Cu alloys （7075 and 7055） during aging has been studied by synchrotron-radiation small angle X-ray scattering （SAXS）.The results show that the precipitates are only a few nanorneters for both alloys ageing even at higher temperature of 160℃ for 72 h （4.44 and 5.82 nm, respectively）. The maximum of the precipitate volume fraction increases with in creasing Zn content and is about 0.023-0.028 and 0.052-0.054, respectively. The coarsening of precipitate is consistent with LSW （Lifshitz-Slyozov-Wagner） model even at the initial stage where volume fraction is still varying.The activation energy of coarsening regime has been determined to be about 1.22±0.02 eV and 1.25±0.02 eV for alloys 7075 and 7055, respectively.展开更多
文摘The alloy （AI-Cu-Mg） alloy important one dating back to the series （2xxx） where copper foundries basic element which represents the number （2）, the study relied on foundries add elements boron （B） and titanium （Ti） and then use a heat treatment （homogenizing process） to improve the corrosion resistance in saline （NaC1 3.5%） of the base alloy （A1-Cu-Mg）, was prepared four types of alloys （A, B, C, D） depending on the chemical composition. The results showed that the corrosion resistance in saline solution was the best resistance in the alloy （D） （A1-2% Cu-2% Mg-0.1% B-1.0% Ti） compared with the rest of bullion when an examination of corrosion of the alloy prepared after homogenizing. But by examining the surface roughness of the alloy ingot turned out that （D） is softer than the rest of the surface alloys and this is due to the addition of boron and titanium together increases surface smoothness in alloys because it works to reduce the grain size.
基金This research was supported by the National Key Fun-damental Research Project of China(No.G19990649)National“863”High Technology Program of China(No.2001 A A332030).
文摘The evolution of microstructure parameters （precipitate size and volume fraction） for two types of Al-Zn-Mg-Cu alloys （7075 and 7055） during aging has been studied by synchrotron-radiation small angle X-ray scattering （SAXS）.The results show that the precipitates are only a few nanorneters for both alloys ageing even at higher temperature of 160℃ for 72 h （4.44 and 5.82 nm, respectively）. The maximum of the precipitate volume fraction increases with in creasing Zn content and is about 0.023-0.028 and 0.052-0.054, respectively. The coarsening of precipitate is consistent with LSW （Lifshitz-Slyozov-Wagner） model even at the initial stage where volume fraction is still varying.The activation energy of coarsening regime has been determined to be about 1.22±0.02 eV and 1.25±0.02 eV for alloys 7075 and 7055, respectively.
