(合肥工業(yè)大學(xué) 材料科學(xué)與工程學(xué)院，合肥 230009)
摘 要: 在380 ℃變形條件下對不同高徑比的Al-Zn-Mg-Cu-Zr合金試樣進(jìn)行高壓扭轉(zhuǎn)實(shí)驗(yàn)，借助于EBSD和XRD技術(shù)分析變形Al-Zn-Mg-Cu-Zr合金的顯微組織、第二相粒子和織構(gòu)的演變規(guī)律。結(jié)果表明：在高壓扭轉(zhuǎn)過程中，大量第二相粒子從過飽和Al基體中脫溶析出，顯微組織明顯細(xì)化，在部分三叉晶界處出現(xiàn)了細(xì)小的動態(tài)再結(jié)晶組織；材料織構(gòu)強(qiáng)度隨著高徑比的減小而減弱；當(dāng)高徑比為0.20時，晶粒的擇優(yōu)取向方向也發(fā)生了明顯變化，晶粒在á102？、á111？方向上出現(xiàn)了擇優(yōu)取向。
關(guān)鍵字: Al-Zn-Mg-Cu-Zr合金；高壓扭轉(zhuǎn)；顯微組織；織構(gòu)；高徑比
（School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009, China）
Abstract:Al-Zn-Mg-Cu-Zr alloys with different height-diameter ratios were deformed by high pressure torsion at 380 ℃. The evolution of microstructures, second-phase particles and textures were studied by electron backscattered diffractometry (EBSD) and X-ray diffractometry (XRD). The results show that a large number of second-phase particles precipitate from supersaturated Al matrix, the microstructures are significantly refined, fine dynamic recrystallization structure occurs at the trigeminal grain boundaries. The density of textures reduces with height-diameter ratios decreasing. When the height-diameter ratio decreases to 0.20, the preferred orientation direction of grains has also undergone a significant change, it occurs on the direction of á102？ and á111？.
Key words: Al-Zn-Mg-Cu-Zr alloy; high pressure torsion; microstructure; texture; height-diameter ratio
