大规格损伤容限钛合金TC4-DT的研制及应用

为了满足新一代战斗机对大规格损伤容限钛合金的需求，开展了TC4-DT钛合金大规格棒材与锻坯的成分与组织控制、大型锻件热处理过程中的显微组织控制、材料与锻件的制造过程控制、零件的疲劳强化等研究。经过大型铸锭熔炼、大规格棒材和锻坯试制、大厚度锻件试制、结构设计与制造，结果表明：损伤容限钛合金TC4-DT大型铸锭的成分均匀、大型锻坯和大厚度锻件的抗拉强度变异系数降至约2%，激光冲击、喷丸和冷挤压等对该合金的寿命增益效果显著。损伤容限钛合金TC4-DT在新一代战斗机上获得了广泛应用。

Development and application of large-scale damage tolerance titanium alloy TC4-DT

To meet the need of large-scale damage tolerance titanium alloy for new generation fighter, this paper examines the TC4-DT titanium alloy’s composition and macrostructure control of large-scale bar and forging stock, the microstructure control during heat treatment process of large-scale forgings, the manufacturing process control of material and forgings, and the fatigue strengthening of parts. The results of large-scale ingot melting, large-scale bar and forging stock trail production, heavy section forging trail production, and structural design and manufacture show that the damage tolerance titanium alloy TC4-DT’s composition of large-scale ingots is homogeneous and the tensile strength coefficient variation of large-scale forging stocks and heavy section forgings can be reduced to about 2%. The impacts of laser shock peening, shot peening, and cold extrusion have remarkable life increment of the titanium alloy. The damage tolerance titanium alloy TC4-DT has been widely applied on new generation fighters.