Nb-Ti-ZrB₂ metal matrix ceramic composites with a fixed atomic ratio Nb/Ti = 2/1 and ZrB₂ volume fraction changing from 0, 11 vol%, 23 vol% to 36 vol% were hot pressed at 1600 °C under 30 MPa. The influence of ZrB₂ content and Ti addition on the phase constitution, microstructure evolution, toughening mechanisms and strengthening mechanisms were investigated. It was shown that the formation of in situ Nb-rich (Ti,Nb)B and Ti-rich (Nb,Ti)B was attributed to a high mutual solubility of monoborides and the amount of niobium and titanium borides increased with increasing ZrB₂ content. The needle-shaped (Ti,Nb)B phase weakened the damage to fracture toughness caused by ZrB₂ particle fracture due to crack bridging, crack defection and the pull-out toughening mechanisms. The highest fracture toughness of the Nb-Ti-ZrB₂ composites was 12.0 MPa·m^1/2. The stiff (Nb,Ti)B phase acted as a strong obstacle to the dislocation motion, leading to dislocation pile-up and enhancing the strength of the Nb-Ti-ZrB₂ composites during compression tests. However, stress concentration around the needle-shaped (Ti,Nb)B phase easily leads to crack initiation and extension, resulting in decreased strength. The yield strength of Nb-Ti-ZrB₂ composites ranged from 657.3 MPa to 1783.0 MPa owing to the combined influence of the strenghening mechanism caused by (Nb,Ti)B and the weakening mechanism caused by (Ti,Nb)B. The compressive deformation and failure process were also discussed in detail in this study.

在1600°C下将具有固定原子比Nb / Ti = 2/1和ZrB ₂体积分数从0、11 vol％，23 vol％更改为36 vol％的Nb-Ti-ZrB ₂金属基陶瓷复合材料进行热压30兆帕。研究了ZrB ₂含量和Ti添加量对相组成，组织演变，增韧机理和强化机理的影响。结果表明，原位富Nb（Ti，Nb）B和富Ti（Nb，Ti）B的形成归因于单硼化物的高互溶性，铌和硼化钛的数量随ZrB _2的增加而增加。内容。针状（Ti，Nb）B相减弱了ZrB ₂对断裂韧性的破坏由于裂纹桥接，裂纹缺陷和拉拔增韧机制而导致的颗粒断裂。Nb-Ti-ZrB ₂复合材料的最高断裂韧性为12.0 MPa·m ^1/2。刚性（Nb，Ti）B相成为位错运动的强烈障碍，导致位错堆积，并在压缩测试过程中增强了Nb-Ti-ZrB ₂复合材料的强度。但是，针状（Ti，Nb）B相周围的应力集中容易导致裂纹的产生和扩展，从而导致强度降低。Nb-Ti-ZrB ₂的屈服强度由于（Nb，Ti）B引起的强化机理和（Ti，Nb）B引起的弱化机理的综合影响，复合材料的应力范围为657.3 MPa至1783.0 MPa。本研究还详细讨论了压缩变形和破坏过程。