中文摘要：

通过机械合金化＋热压烧结工艺制备了Cr-10Ta和Cr-10Ta-20Mo合金,研究了添加20%Mo对Laves相Cr-Ta合金组织及室温力学性能的影响。结果表明,Cr、Ta和Mo元素粉经球磨25 h后在1350℃×1 h热压工艺下可获得组织细小均匀的高致密度Cr-10Ta和Cr-10Ta-20Mo合金。Cr-10Ta中生成的Laves相Cr2Ta是室温下稳定的C15结构,而添加20%Mo会使合金中生成的Laves相Cr2Ta发生相转变,形成亚稳态的C14型Laves相。所制备的Cr-10Ta-20Mo合金表现出良好的细晶和合金化强韧化效果,室温下的硬度为6.89 GPa,断裂韧性大于7.91 MPa·m^1/2,屈服强度和抗压强度分别达2635、3364 MPa,压缩应变为6.7%。

英文摘要：

Cr-10 Ta and Cr-10Ta-20 Mo alloys were prepared by mechanical alloying and hot-pressing sintering technique.The effects of 20% Mo addition on the microstructure and room temperature mechanical properties of Laves phase Cr-Ta alloy were investigated. The results indicate that the high dense Cr-10 Ta and Cr-10Ta-20 Mo alloys with fine and homogeneous microstructure could be synthesized successfully by Cr, Ta and Mo element powders ball milling for 25 h and hot pressing at1350 ℃ for 1 h. The Laves phase Cr2Ta appearing in Cr-10 Ta alloy is room-temperature stable C15 structure. By adding 20%into Cr-10 Ta alloy, the phase transition of Laves phase Cr2Ta appears in the Cr-10Ta-20 Mo alloy, and then, the unstable C14 Laves phase forms in Cr-10Ta-20 Mo alloy. The prepared Cr-10Ta-20 Mo alloy has a good strengthening and toughening effect by fine grained and alloying. The hardness of Cr-10Ta-20 Mo alloy at room temperature is 6.89 GPa,the fracture toughness is above 7.91 MPa·m^1/2, the yield strength and compressive strength reaches 2635 MPa and 3364 MPa, respectively, and the compressive strain is 6.7%.