(中南大学 轻质高强结构材料国家级重点实验室，长沙 410083)
摘 要: 以高纯钨粉和高纯X粉为原料，通过放电等离子烧结技术 (SPS)制备了不同X含量的W-X合金材料，并结合X射线衍射仪、扫描电镜、透射电镜等分析手段，研究X含量对W-X合金材料微观组织及强韧性的影响。结果表明：W-X合金材料的主要相组成为W-X固溶体和X的氧化产物X2O5；X元素的加入改变了纯钨的变形机制，在螺位错的基础上，出现了刃位错；随着X含量的增加，X固溶到钨晶粒中的比例逐渐增大，晶粒尺寸发生长大；随着X含量的增加，W-X合金材料的相对密度先增加后趋于稳定，压缩强度呈现先增大后减小的规律；当X含量为30%(质量分数)时，W-X合金呈现最佳性能，压缩强度达2044 MPa，压缩应变达24%。
关键字: 高强；高韧；钨；固溶体；放电等离子烧结
（National Key Laboratory of Science and Technology for National Defence on High-strength Structural Materials, Central South University, Changsha 410083, China）
Abstract:W-X alloy was prepared by spark plasma sintering (SPS) with high purity tungsten powder and X powder. The effect of X content on the solid solution characteristics and strength and toughness of W-X alloy was studied by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS). The results show that the main phases of the W-X alloy are W-X solid solution and X2O5. The addition of X changes the deformation mechanism of pure tungsten. On the basis of screw dislocation, the edge dislocations appear. The amount of X solid solution into tungsten grain increases gradually with the increase of X content. The grain size grows up with the increase of X content，which seriously reduces the mechanical properties of the W-X alloy. The relative density of the W-X alloy gradually increases with the increase of X content. The compressive strength of W-X alloy first increases and then decreases with the increase of X content. When the X content is 30% (mass fraction), the performance of W-X is the best, the compressive strength is 2044 MPa and the fracture strain is 24%.
Key words: high strength; high toughness; tungsten; solid solution; spark plasma sintering
