TA15钛合金大锻件两种模锻工艺的组织性能对比研究Comparison of Microstructure and Mechanical Properties for TA15 Titanium Alloy Large Forgings under Two Die-forging Equipments

采用相同规格TA15棒材分别利用800MN模锻压力机、1MJ对击模锻锤制备同种形状钛合金大型航空模锻件,对两种模锻条件下的锻件组织及力学性能进行了对比研究。结果表明:800MN制备的锻件塑性流线分布好,每火次变形量大、变形速率低,比1MJ锻件再结晶晶粒尺寸小、等轴初生α相比例高且颗粒更加细小,室温、500℃高温拉伸性能以及冲击韧性和断裂韧性均有所提高。

800MN die-forging press and 1MJ die-forging hammer were employed on TA15 titanium alloy to produce large aerial forgings. Microstructure and mechanical properties of TA15 forgings under the two forging equipments were investigated and compared. Results show that the forgings under 800MN die-forging press have a preferable plastic flow. The 800MN die-forging press will cause lager deformation and lower strain rate during every heating. The forgings under 800MN die-forging press have more fine grain size after recrystallization compared with those under 1MJ die-forging hammer. It also had a higher percentage of primary alpha phase as well as more fine α precipitation under 800MN die-forging press. As a result, its tensile properties and impact toughness and fracture toughness of the forgings are higher than those under 1MJ forging. Furthermore, the costs and quality are more ideal under 800MN die-forging press because the strain and strain rate are more controllable and the forging times are less.