TB17钛合金β相区晶粒长大行为

摘要

The β grain growth behavior was investigated on a new high strength and high toughness TB17 titanium alloy bar. The β grain evolution of TB17 titanium alloy at various heat treatment temperature and time has been studied. The grain growth exponents were calculated by Beck equation and grain growth activation energy was calculated by Arrhenius equation. The results show that the heat treatment temperature and time have significant effect on the βgrain growth of TB17 titanium alloy. The heat treatment temperatures range from 860 ℃ to 1 045 ℃, the kinetics ofβ grain growth curves approximate fit the exponential relationship. The β grain growth exponents range from 0. 12 to 0. 23. Heat treated for short time, the kinetics factors are main influence for the β grain growth, while long time heat treatment the kinetics factors effect decrease. The β grain growth activation energy is 48. 26 kJ/mol.%以新型超高强韧TB17钛合金棒材为研究对象，研究了TB17钛合金β相区晶粒的长大行为。考察了TB17钛合金在不同温度和保温时间的条件下，β晶粒尺寸的变化，通过Beck公式计算了晶粒长大参数，采Arrhenius公式计算了晶粒长大激活能。结果表明，加热温度及保温时间对TB17钛合金β晶粒长大行为具有重要影响。在860~1045℃进行等温加热， TB17钛合金β晶粒等温长大曲线近似符合指数关系，β晶粒长大指数n在0．12~0．23之间。短时保温，β晶粒长大过程中动力学影响因素占主导作用，延长保温时间，动力学影响因素作用降低。 TB17钛合金β晶粒长大激活能为48．26 kJ/mol。