多道次搅拌摩擦加工对5083-O铝合金组织性能的影响

在不同轴肩直径、搅拌头转速和搅拌头行进速度下，对27mm厚5083-O铝合金进行了多道次搅拌摩擦加工(multi passfrictionstirprocessing)，搭接率为100%，共进行3道次搅拌摩擦加工.研究结果表明，加工区由细小的再结晶组织组成；随着加工道次的增加，加工区内部缺陷体积减少，晶粒进一步细化，析出相细化并均匀分布，力学性能提高，加工区最高抗拉强度可达360MPa，延伸率也优于母材；其中，第二道次加工对材料组织和性能的影响最为明显.

Effect of Multi pass Friction Stir Processing on Microstructures and Mechanical Properties of 5083 O Aluminum Alloy

Multi pass friction stir processing (3 pass FSP with 100% overlap) was conducted under different diameters of shoulders， rotation speeds and travel speeds to investigate the effect of processing parameters on the microstructures and the mechanical properties of 5083 O aluminum alloy. The results showed that the fine and dynamically recrystallized grains are observed in the FSP zone. With increasing the number of passes， the grain size and the tunnel defects decrease， the second phase particles are refined and distributed uniformity， the ultimate tensile strength reaches up to 360 MPa， and the elongation is higher than that of the base metal. The effect of the 2nd pass on the microstructures and mechanical properties is most obvious.