冷轧纯钛带各向异性研究

文章通过对1.0 mm冷轧纯钛带组织和力学性能各向异性的研究分析,结果表明,1.0 mm冷轧钛带采用退火温度630℃,保温20 h热处理,横向(TD)、沿轧制方向(RD)和45°3个方向均为完全再结晶等轴组织,对材料冲压成形性能无明显影响;1^(#)、2^(#)和3^(#)批次1.0 mm冷轧纯钛带TD、RD和45°3个方向的拉伸性能和应力-应变变化规律基本一致,因冷轧钛带沿轧制方向单向变形,造成材料TD和RD 2个方向存在明显的各向异性;对比TD、RD和45°3个方向的塑性应变比r值和拉伸硬化指数n值的变化规律,在冲压成型过程,材料TD方向更容易产生冲压裂现象,TD和RD 2个方向均出现轻微制耳。

In this paper, the anisotropy of microstructure and mechanical properties of 1.0 mm cold rolled pure titanium strip is studied and analyzed. The results show that the annealing temperature of 1.0 mm cold rolled titanium strip is 630 ℃,the heat preservation time is 20 h, and the three directions of TD, RD and 45° are fully recrystallized, equiaxed structures,which has no obvious effect on the stamping formability of the material;the 1^(#), 2^(#)and 3^(#)batches of 1.0 mm cold-rolled titanium strips have basically the same tensile properties and stress-strain variation laws in TD, RD and 45° directions. Due to the unidirectional deformation of cold-rolled titanium strips along the rolling direction, there is obvious anisotropy in TD and RD directions. Compared with the variation rules of plastic strain ratio r and tensile hardening index n in TD, RD and45° directions, the stamping cracking phenomenon is more likely to occur in TD direction in the stamping process, and slight earing occurs in both TD and RD directions.