【摘要】 WMoNbCrTi高熵合金是一种极具应用潜力的高温结构材料，添加Si有望提高其综合力学性能。以高能球磨粉末为原料，采用放电等离子烧结技术制备了WMoNbCrTiSi_x（x=0、0.1、0.25和0.5）高熵合金，研究Si含量对其微观组织和力学性能的影响。结果表明：加入Si后高熵合金的组织由BCC固溶体、Laves相和硅化物组成。当x=0.1时，Si主要形成Ti₅Si₃,当x=0.25时，大部分Si与Ti形成Ti₅Si₃,少部分Si与Nb形成Nb₃Si,当x=0.5时，Si主要形成Ti₅Si₃、Nb₃Si和Cr₃Si。当x从0增加到0.5时，WMoNbCrTiSi_x高熵合金的硬度由9.84 GPa增加到13.46 GPa,断裂韧性从6.68 MPa·m^1/2下降到4.72 MPa·m^1/2。WMoNbCrTiSi高熵合金中的硅化物提高了硬度，降低了断裂韧性。当x从0增加到0.5时，最大压缩应变由9.1%提高到13.2%,压缩断裂强度由1758 MPa提高到2448 MPa,这主要是由于晶粒细化和硅化物的共同作用所致。更多还原

【Abstract】 WMoNbCrTi high-entropy alloy is a high temperature structural material with great application potential. The addition of Si is expected to improve its comprehensive mechanical properties. WMoNbCrTiSi_x（x=0,0.1,0.25 and 0.5） high-entropy alloys were prepared by spark plasma sintering with high-energy ball milling powders as raw materials, and the effect of Si content on its microstructure and mechanical properties was studied. The results show that the microstructure of the high-entropy alloys after adding Si is composed of BCC solid solution, Laves phase and silicide. When x=0.1, Si mainly forms Ti₅Si₃. When x=0.25, most Si forms Ti₅Si₃ with Ti, and a few of Si forms Nb₃Si with Nb. When x=0.5, Si mainly forms Ti₅Si₃, Nb₃Si and Cr₃Si. When x increases from 0 to 0.5, the hardness of the WMoNbCrTiSi_x high-entropy alloys increases from 9.84 GPa to 13.46 GPa, and the fracture toughness decreases from 6.68 MPa·m^1/2 to 4.72 MPa·m^1/2. The silicide in the WMoNbCrTiSi high-entropy alloys increases the hardness and reduces the fracture toughness. When x increases from 0 to 0.5, the maximum compressive strain of the alloys increases from 9.1% to 13.2%, and the compressive fracture strength increases from 1758 MPa to 2448 MPa, which is mainly due to the combined effect of grain refinement and silicide.更多还原