单晶铜在ECAP过程中的织构转变和强化行为（英文）

Texture Evolution and Strengthening Behavior of Single Crystal Copper During Equal Channel Angular Pressing

由于优异的导电和导热性能,单晶铜在各个关键领域得到了广泛的应用。然而,较低的强度严重限制了其在更广阔领域的发展和使用。利用ECAP对单晶铜进行强韧化调控,同时探索变形路径对材料性能强化机理的影响。采用电子背散射衍射来对ECAP变形过程中单晶铜的织构进行检测。模具的内角Ф=120°,外角ψ=37°。同时检测强化后材料的强度和延伸率。结果表明:5道次挤压后,A路径,Bc路径和C路径的强度分别为405、395、385 MPa,延伸率分别为30%、30%、27.9%。6道次挤压后,A路径的织构从原始的{111}<112>变为{112}<110>以及较弱的{110}<112>两种织构;Bc路径为{001}<110>织构;而C路径的织构发生了明显分散,出现多种织构并存的情况。在挤压过程中材料的导电性只有轻微的降低。可以看出,在合适的应变量下,ECAP可以使单晶铜强度明显提高而且导电性损失很小。同时,采用不同的挤压路径可以显著影响材料的性能。

ECAP was adopted in this study to reinforce the single crystal copper by route A, Bc and C, and the effect of different routes was studied. The texture of single crystal copper during ECAP with a die channel angle Ф=120° and ψ=37° was investigated by electron backscatter diffraction(EBSD). At the same time, the elongation and strength of the material were tested. The results show that after 5 passes, the tensile strength and elongation of route A, Bc and C are 405 MPa and 30%, 395 MPa and 26.7%, and 385 MPa and 27.9%, respectively. After 6 passes, the textures, which are formed using the route A to complete the extrusion, are translated from the initial {111}<112> texture to {112}<110> and weaker {110}<112> textures. The texture of route Bc is {001}<110>, while the texture of route C is dispersed and the coexistence of many kinds of textures appears. Meanwhile, the conductivity of the materials decreases little. It can be seen that ECAP can significantly reinforce the material without obviously decreasing the conductivity. Different extrusion routes can remarkably influence the properties of the material.