新型TC21钛合金热处理工艺参数与显微组织演变的关系研究

TC21钛合金是新型的高强韧损伤容限型钛合金，其模锻件为网篮组织，锻后热处理工艺采用双重退火工艺。本研究采用金相法、SEM等方法系统研究了TC21钛合金模锻件的锻后热处理工艺和显微组织演变规律。试验分析了TC21钛合金模锻件锻后第1次退火加热温度、第2次退火加热温度和保温时间等工艺参数条件下的初生α相数量、形状以及网篮组织形貌特征的变化规律，为TC21钛合金模锻件获得高强、高韧和损伤容限优良综合性能奠定基础。

Study on the Relationship between Heat Treatment Parameters and Microstructures Evolvement of New Type TC21 Titanium Alloy

TC21 titanium alloy is a new type of titanium alloy of high strength, high toughness and damage tolerance. TC21 titanium alloy forgings with lamellar microstructure will be the right microstructure after dual annealing heat treatment to obtain high fracture toughness and low fatigue crack propagation rate, which are needed by design of excellent damage tolerance and long duration. By means of photographic and SEM techniques, the relationship between heat treatment parameters and microstructures evolvement of TC21 titanium alloy forgings has been studied. The effect-of, first annealing temperature and second annealing temperature and time on the amount and shape of lameUar structure has also been analyzed, which could lay a solid technological foundation for TC21 titanium alloy forgings to achieve high strength, high toughness and damage tolerance properties.