Incoherent interphases and oxygen segregation at the grain boundaries (GBs) significantly deteriorate the strength of Mo-based alloys. In this study, a new additive, LaB₆, was proposed to enhance the mechanical properties. It was found that LaB₆ reacted with the matrix to generate coherent La₂O₃, volatile B₂O₃ and tiny MoB in situ during sintering. The addition of LaB₆ does not increase strength by itself, but can limit grain growth and construct a coherent interface between the as-obtained La₂O₃ and Mo matrix. More importantly, the oxygen impurity is removed by B in the form of B₂O₃, which purifies the GBs. As a result, the as-sintered Mo-La-B billets present an extremely high ultimate tensile strength of 965 MPa, which is among the best recorded values for all sintered Mo-based alloys. The enhanced strength can be attributed to the refined grain size, coherent phase interface, and purified GBs.

晶界 (GB) 处的不相干界面和氧偏析显着降低了 Mo 基合金的强度。在这项研究中，提出了一种新的添加剂 LaB ₆来提高机械性能。发现LaB _{6在烧结过程中与基体发生反应}，原位生成共格的La ₂ O ₃、挥发性的B ₂ O ₃和微小的MoB 。LaB ₆的添加本身不会增加强度，但可以限制晶粒生长并在所获得的La ₂ O ₃和Mo基体之间构建共格界面。更重要的是，氧杂质以B的形式被B除去₂ O ₃，净化GB。因此，烧结态 Mo-La-B 坯料具有 965 MPa 的极高极限抗拉强度，这是所有烧结钼基合金的最佳记录值之一。增强的强度可归因于细化的晶粒尺寸、共格相界面和纯化的晶界。