Epoxy composites reinforced with three different shapes of Al₂O₃ nanoparticles were synthesized by instant cross-linking process. Out of three types of Al₂O₃ particles, two were of rod shape particles termed as large nano rod (diameter 2–4 nm and length 100–200 nm), and small nano rod (diameter of 5–10 nm and length less than 50 nm) and third particle was spherical in shape (diameter of 27–43 nm). 0.5, 1.0, and 1.5 wt.%. of reinforcement was maintained constant. Reinforcement of low (1.0) wt.% of spherical Al₂O₃ nanoparticles is more promising in enhancing tensile strength and failure strain of epoxy composite. At 1.0 wt.% reinforcement of spherical Al₂O₃ nanoparticles, tensile strength and failure strain are improved by 10% and 29%, respectively. Quasi-static fracture toughness of epoxy composite was improved by reinforcement of all three types of Al₂O₃ nanoparticles. Fracture toughness of epoxy composite was enhanced by 52% at 1.5 wt.% inclusion of large Al₂O₃ nano rod. Crack deflection and crack bridging were the micro-mechanics accountable for improved fracture toughness of spherical Al₂O₃ composite. Crack tilting and twisting, particle pull out, along with crack deflection were the main contributors for increased fracture toughness of composites of Al₂O₃ nano rods.

通过即时交联工艺合成了三种不同形状的Al ₂ O ₃纳米颗粒增强的环氧树脂复合材料。在三种类型的Al ₂ O ₃颗粒中，两种是棒状颗粒，分别称为大纳米棒（直径2-4 nm，长度100-200 nm）和小纳米棒（直径5-10 nm，长度短）大于50 nm），第三个粒子呈球形（直径27-43 nm）。0.5、1.0和1.5重量％。钢筋的数量保持恒定。低（1.0）wt。％的球形Al ₂ O ₃纳米颗粒的增强在增强环氧复合材料的拉伸强度和破坏应变方面更有希望。在1.0 wt。％的条件下增强球形Al ₂ O_使用3种纳米颗粒，抗张强度和破坏应变分别提高了10％和29％。通过增强所有三种类型的Al ₂ O ₃纳米颗粒，可以改善环氧复合材料的准静态断裂韧性。在包含1.5 wt。％的大型Al ₂ O ₃纳米棒的情况下，环氧复合材料的断裂韧性提高了52％。裂纹变形和裂纹桥接是改善球形Al ₂ O ₃复合材料断裂韧性的微观机制。裂纹的倾斜和扭曲，颗粒的拉出以及裂纹的弯曲是增加Al ₂ O ₃复合材料断裂韧性的主要因素 纳米棒。