2相界面對TiAl合金在轟擊過程中的變形機制和轟擊后力學(xué)性能的影響，通過分子動力學(xué)來模擬超音速微粒轟擊雙相TiAl合金的過程。結(jié)果表明：γ/α2不同厚度比模型的沖擊變形機制不同，變形主要集中在γ相和界面處。隨著γ相厚度的減小，與相界面接觸的位錯首先被界面處的失配位錯網(wǎng)絡(luò)吸收，然后在相界面處成核，最終穿過相界面進入α2相。沖擊過程中產(chǎn)生的位錯以Shockley位錯為主，試樣中形成了不完全層錯四面體。沖擊之后分別使用單軸拉伸模擬和納米壓痕模擬，測定了試樣的強度和表面硬度。拉伸過程中相變、孿晶和層錯是不同厚度比試樣的主要變形機制。與其他試樣相比，厚度比為1:3的雙相TiAl合金在沖擊后具有最高的屈服強度、硬度和彈性模量。;In order to investigate the effect of γ/α2 phase interface on the deformation mechanism and mechanical properties of TiAl alloy during bombardment process, the supersonic fine particle bombardment of dual-phase TiAl alloy was simulated by molecular dynamics. Results show that the impact deformation mechanisms of γ/α2 models with different thickness ratios are different, and the deformation is mainly concentrated at the γ phase and interface. With decreasing the γ phase thickness, the dislocations in contact with the phase interface are firstly absorbed by the mismatched dislocation network, then they are nucleated at the phase interface, and eventually the dislocations pass through the phase interface, entering the α2 phase. Shockley dislocation is the main dislocation type in the impact process, and incomplete stacking fault tetrahedron forms in the specimen. After impact, uniaxial tensile simulation and nano-indentation simulation were conducted to measure the strength and surface hardness of the specimens. The main deformation mechanisms of specimens with different thickness ratios are the phase transformation, twins, and stacking faults during tensile process. Compared with other specimens, TiAl alloy with thickness ratio of 1:3 has the highest yield strength, the highest hardness, and the highest elastic modulus after impact."/>
3Al;力學(xué)性能;塑性變形;molecular dynamics;phase interface;TiAl/Ti3Al;mechanical properties;plastic deformation"/>