纳米结构多主元合金的力学行为及强塑化机制

刘畅, 吴戈, 吕坚

Nanostructural Multi-Principal-Element Alloys: Mechanical Properties and Toughening Mechanisms

LIU Chang, WU Ge, LU Jian

图4 高强塑性NiCo纳米晶合金^[56]

Fig.4 NiCo nanocrystalline alloy with ultrahigh strength and large ductility^[56]
(a) atom probe tomography showing compositional undulation in the NiCo alloy
(b) stacking fault energy (γ_SFE), unstable stacking fault energy (γ_USFE), and their difference as a function of Co content in the Ni-Co alloy
(c) glide distance as a function of time for a <110>/2 dissociated dislocation under a constant shear stress of

~

120 MPa in the compositionally undulated NiCo alloy, homogeneous NiCo alloy, and Ni
(d) HRTEM image of representative dissociated dislocations stored in the NiCo alloy after tension (SF—stacking fault)
(e) inverse fast Fourier-filtered image presenting Lomer locks (in red circles)
(f) HRTEM image showing Lomer locks (in red circles) and Lomer-Cottrell (LC) locks in the NiCo alloy after tension (Inset is the HAADF-STEM image showing the atomic structure of a representative Lomer lock. b₁- b₃ show the Burgers vectors)