【摘要】 采用激光金属沉积工艺对成分重组设计后的Nb-Mo-Ta-W系难熔高熵合金进行成形制备，利用X射线衍射仪和扫描电子显微镜对（NbMoTa）₉₀W₁₀和（NbMoTaTi）₉₀W₁₀两种高熵合金的相结构、缺陷与微观组织进行了表征分析，并通过多功能力学试验机对两种合金进行室温拉伸性能测试。结果表明：（NbMoTa）₉₀W₁₀和（NbMoTaTi）₉₀W₁₀两种高熵合金均为单相体心立方结构；Ti元素在Nb-Mo-Ta-W系合金中的晶界处形成了“液态薄膜”，可实现对沿晶裂纹的良好抑制；冶金缺陷的减少以及Ti元素引入的晶格畸变效应，（NbMoTaTi）₉₀W₁₀高熵合金的室温力学性能提升，屈服强度达到1156 MPa。更多还原

【Abstract】 The Nb-Mo-Ta-W series refractory high-entropy alloys with composition recombination design were manufactured by laser metal deposition process. The phase structure, defects and microstructure of（NbMoTa）₉₀W₁₀ and（NbMoTaTi）₉₀W₁₀ highentropy alloys were characterized and analyzed by X-ray diffraction and scanning electron microscope. The tensile properties of the two alloys were tested at room temperature by multifunctional mechanical testing machine. The results showed that both（NbMoTa）₉₀W₁₀ and（NbMoTaTi）₉₀W₁₀ high-entropy alloys are single-phase body centered cubic structures. Ti element forms a "liquid film" at the grain boundaries in Nb-Mo-Ta-W series alloy, which can effectively suppress intergranular cracks. Due to the reduction of metallurgical defects and the lattice distortion effect, the mechanical property of（ NbMoTaTi） ₉₀W₁₀ high-entropy alloy at room temperature is improved, and the yield strength reaches 1156 MPa.更多还原