7A60铝合金高压扭转变形微观组织及力学性能分析
发布时间：2018-09-03 18:01
【摘要】：对不同高径比H/D的7A60铝合金坯料进行高压扭转实验,借助于EBSD技术分析了变形7A60铝合金微观组织(晶界取向差、晶粒取向)演变规律,同时对变形7A60铝合金进行拉伸实验和断口扫描,分析7A60铝合金的抗拉强度、断裂方式和断裂机理。研究结果表明:高压扭转变形后7A60铝合金晶粒发生了明显破碎细化,当高径比H/D为0.25时,晶粒取向沿001、101方向;当进一步减小高径比H/D时,在三叉晶界处出现了细小的动态再结晶晶粒,取向角在2°≤θ≤5°范围内的小角度晶界比例较大,同一晶粒内部出现了颜色渐变区,大部分晶粒取向沿111方向;高压扭转变形后7A60铝合金抗拉强度明显提高,最高抗拉强度达到了751 MPa,提升幅度达到了20.74%,在强度得到大幅提高的同时伸长率也得到了较好的保持,最高伸长率为14%;高压扭转变形后7A60铝合金断裂方式为塑性断裂,断裂机理属于微孔连接断裂。
[Abstract]:The high pressure torsion experiment of 7A60 aluminum alloy billets with different aspect ratio H / D was carried out. The evolution law of microstructure (grain boundary orientation, grain orientation) of deformed 7A60 aluminum alloy was analyzed by means of EBSD technique. The tensile strength, fracture mode and fracture mechanism of 7A60 aluminum alloy were analyzed by tensile test and fracture scanning. The results show that the grain size of 7A60 aluminum alloy is obviously broken and refined after high pressure torsional deformation. When the aspect ratio H / D is 0. 25, the grain orientation is along the 001101 direction, and when the aspect ratio H / D is further reduced, There are fine dynamic recrystallized grains at the tripod grain boundary. The ratio of small angle grain boundary with orientation angle is larger in the range of 2 掳鈮，
本文编号：2220749
[Abstract]:The high pressure torsion experiment of 7A60 aluminum alloy billets with different aspect ratio H / D was carried out. The evolution law of microstructure (grain boundary orientation, grain orientation) of deformed 7A60 aluminum alloy was analyzed by means of EBSD technique. The tensile strength, fracture mode and fracture mechanism of 7A60 aluminum alloy were analyzed by tensile test and fracture scanning. The results show that the grain size of 7A60 aluminum alloy is obviously broken and refined after high pressure torsional deformation. When the aspect ratio H / D is 0. 25, the grain orientation is along the 001101 direction, and when the aspect ratio H / D is further reduced, There are fine dynamic recrystallized grains at the tripod grain boundary. The ratio of small angle grain boundary with orientation angle is larger in the range of 2 掳鈮，
本文编号：2220749
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