(1. 中南大學(xué) 材料科學(xué)與工程學(xué)院，長沙 410083；
2. 中南大學(xué) 有色金屬材料科學(xué)與工程教育部重點(diǎn)實(shí)驗(yàn)室，長沙 410012)
摘 要: 采用透射電鏡、拉伸試驗(yàn)、剝落腐蝕試驗(yàn)等手段，研究7055鋁合金在回歸時(shí)效階段的晶界η相形貌、尺寸、間距及其粗化動(dòng)力學(xué)行為，以及對最終材料性能的影響。結(jié)果表明：隨著回歸溫度的升高或回歸時(shí)間的延長，晶界η相不斷粗化，間距也不斷增大；且回歸溫度越高，晶界η相粗化速率越快。在本實(shí)驗(yàn)條件下，該合金晶界η相的粗化激活能Q=1.13 eV，據(jù)此建立晶界相粗化動(dòng)力學(xué)模型。
關(guān)鍵字: 7055鋁合金；回歸時(shí)效；晶界析出相；粗化動(dòng)力學(xué)
（1. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
2. Key Laboratory of Nonferrous Materials Science and Engineering, Ministry of Education,
Central South University, Changsha 410012, China）
Abstract:The morphology and coarsening kinetics of grain boundary precipitates (η) in the regression aging stage of 7055 aluminium alloys were studied by transmission electron microscopy (TEM), and the corresponding effects on the mechanical property and corrosion resistance were measured by tensile tests and exfoliation corrosion tests. The results show that the grain boundary precipitates (η) are coarsened and the inter-space increases with the retrogression temperature or retrogression time increasing. The coarsening rate of η precipitates increases with retrogression temperature increasing. The coarsening activation energy is 1.13 eV, and a modified coarsening kinetics model of grain boundary precipitates was proposed.
Key words: 7055 aluminium alloy; regression aging; grain boundary precipitates; coarsening kinetics
