异步累积叠轧纯铜材的取向变化过程与力学性能

Texture and Mechanical Properties of Pure Copper Deformed by Asymmetrical Accumulative Roll-bonding

室温下对纯铜薄板进行一到六道次的异步累积叠轧变形加工。采用金相显微镜、扫描电镜附带背散射电子衍射、X射线衍射仪附带织构附件及拉伸试验机进行组织、取向观察及力学性能测试,获得铜材异步叠轧过程的显微组织、轧制织构变化过程和力学性能。结果表明:经过六道次的异步累积叠轧变形,由于压缩变形与剪切变形作用,使晶粒细化,铜材晶粒尺寸由30～50μm细化到5μm。异步叠轧过程中出现:{112}〈111〉,{123}〈634〉,{011}〈211〉和{011}〈100〉几种主要组分轧制织构。材料的屈服强度与抗拉强度明显提高,六道次后分别达到348MPa和452MPa。材料的伸长率在二道次后显著下降到2.3%,然后随等效应变的增加略微下降。

Pure copper sheets were prepared by Asymmetrical Accumulative Rolling Bonding（AARB） at room temperature. By optical microscopy, scanning electron microscopy（SEM） with electron back- scattered diffraction（EBSD）,X-ray diffractometer（XRD） with texture accessories and stretch mechan- ics performance tests, the microstructure,texture and mechanical properties of pure copper sheets by AARB were discussed. The results show that after six times of AARB, the grains of copper is refined by compression deformation and shearing deformation , and the average grain size is refined to 5μm. Texture of sample main composed of {112}（111）, {123}〈634）,{011}〈211） and {011}〈100）. Yield strength and tensile strength of sample increase obviously, a0.zand 6b got to 348MPa and 452MPa sepa- rately. The elongation of sample decreases to 2.3 ~ after the second pass, and then it decreases a little with the rise of the equivalent strain.