航空用高强TA18钛合金管材的轧制工艺

Rolling Process of High-Strength TA18 Titanium Alloy Tubes for Aviation

摘要:

通过试制不同规格的TA18实验管材，研究Q值、累积变形率以及退火温度对成品管的显微组织和力学性能的影响。结果表明：当变形率不大于55%，且Q值控制在0.53~1.14时，管材可顺利实现两辊轧制而不出现裂纹。随着变形率的增大，实验管材加工态的强度逐渐升高，塑性下降，但较小的变形率对塑性影响不大。随着退火温度的升高，管材的强度降低，塑性改善，加工硬化效应逐渐消除。另外，过小的变形率会造成管材的再结晶晶粒尺寸分布不均，进而导致塑性较低。经工艺优化，TA18实验管材的力学性能可达：UTS=920 MPa，YS=755 MPa，El=14%

Abstract:

By producing TA18 experimental tubes with different dimension, the effects of Q value, accumulated deformation rate and annealing temperature on the microstructure and mechanical properties of the finished tubes were studied. Results show that the tubes can be rolled successfully in two-roll mill without cracking in surface, when the deformation rate is under 55% and the Q value maintains 0.53~1.14. With the increase of the deformation rate, the strength of the experimental tubes rises gradually while the elongation falls. However, the influence of the minor deformation rate on the elongation is very limited. In addition, the strength of the experimental tubes decreases and the elongation improves with the increase of the annealing temperature. Meanwhile, the work-hardening effect is diminished gradually. It is also found that the recrystallized grain size distribution of the experimental tubes would be non-homogeneous if the deformation rate is too low, which can result in the decrease of the elongation of the tubes annealed. After the process optimizing, the mechanical properties of TA18 experimental tubes can reach UTS=920 MPa, YS=755 MPa and El=14%.