研究了钛合金经冷拉后的变形组织和性能,金相、透镜观察表明,位错滑移是钛合金室温下塑性变形的主导机制.钛合金经过冷拉拔后的组织性能变化可分为3个阶段:第一阶段为快速硬化阶段,以大晶粒的变形为主,位错缠结形成；第二阶段其抗拉强度值增加趋于平缓,近乎于一个平台,部分小晶粒也开始参与变形,位错带形成；第三阶段为应变量大于0.60后,又出现快速硬化阶段,所有晶粒参与变形,低角度几何必须晶界向高角度晶界转变,导致晶粒细化.%The microstructure and properties of Ti6A14V wires after cold drawing are studied. Metal-loscope and transmission electron microscopy reveal that the dislocation gliding is the dominant deformation mechanism in the as-drawn wires. During the cold drawing, the microstructure and properties evolution could be separated into three stages. The initial fast strain hardening is mainly caused by deformation of large grain. In this stage entanglement of dislocations begin to form. The second stage is almost a platform. Partial small grains begin to participate in the deformation, which corresponds to the formation of shear bands. As e>0.60, all grains take part in the deformation and grain refinement is caused by the changing of low-angle geometrically necessary boundaries (GNBs) into high-angle grain boundaries (HAGBs).
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