(1. 大连理工大学 材料科学与工程学院，大连 116024；
2. 大连盛辉钛业有限公司，大连 116600)
摘 要: 分析对比不同工序后医用U型钉用TC4钛合金棒材的组织性能。结果表明：热拔和高温退火工艺对棒材的再结晶组织有明显影响，而双曲线矫直和低温退火工艺对棒材力学性能的影响较大。730~750 ℃高温退火2 h后，热拔材的再结晶程度比较充分；580~700 ℃低温退火2 h后，矫直材的光学显微组织未发生明显变化，但硬度明显减小。在730~750 ℃高温退火、580 ℃低温退火的条件下对棒材的显微组织进行调控，可获得符合医用TC4钛合金力学性能要求的棒材，且由其加工的U型钉缩口尺寸可控制在0.05 mm以下。
关键字: TC4钛合金；U型钉；缩口尺寸；显微组织；力学性能
（1. School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024, China;
2. Dalian Suntec Titanium Co., Ltd., Dalian 116600, China）
Abstract:Comparing with microstructure and mechanical property of TC4 alloy bar after different procedures. The results show that the recrystallization microstructure of the bar is found to be affected significantly by high temperature annealing, while the mechanical property is affected by hyperbola straightening and low temperature annealing. The recrystallization degree of hot drawing bar is sufficient after being annealed at 730-750 ℃ for 2 h. Optical microstructure of straightening bar does not change significantly, but the Vickers hardness decreases evidently after being annealed at 580-700 ℃ for 2 h. When the high and low temperature annealing are performed at 730-750 ℃ and 580 ℃, respectively, the mechanical property of the bar is suitable for the medical TC4 alloy based on the microstructure control. In addition, the necking size of U-shaped nail processed from the bar is desirable to be lower than 0.05 mm.
Key words: TC4 titanium alloy; U-shaped nail; necking size; microstructure; mechanical property
