Brittle matrix is usually toughened by metallic phases to enhance the fracture toughness. In the present study of alumina nickel, composite with 15 wt% of nickel was prepared by sol-gel route by using Al(C₃H₇O)₃, NiCl₂.6H₂O, and dextrose as precursor. The precursor gel composite was reduced by the novel in situ reduction to obtain metallic nickel dispersed in the alumina matrix. Prior to this reduction of NiCl₂.6H₂O, a novel technique of repeated evacuation and purging of the gel was carried out with N₂ in order to replace the air present in the pores of gel, and secondly the in situ reduction was carried out in a charcoal boat in a N₂ atmosphere to generate sufficient reducing atmosphere to prevent reoxidation of metallic Ni. The alumina-nickel nanocomposites were thoroughly investigated by different characterization techniques like X-ray diffraction, Dynamic light scattering, etc. Interestingly, the synthesis of a finer grained alumina-Ni composite was obtained when it was reduced at higher temperature, unlike expected and this phenomenon was explained in the text.

中文翻译：

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溶胶-凝胶法原位还原合成氧化铝-镍纳米复合材料及其表征

脆性基体通常通过金属相增韧，以增强断裂韧性。在目前对氧化铝镍的研究中，以Al（C ₃ H ₇ O）₃，NiCl ₂ .6H ₂ O和葡萄糖为前体，通过溶胶-凝胶法制备了镍含量为15％的复合材料。通过新颖的原位还原将前体凝胶复合材料还原，以获得分散在氧化铝基质中的金属镍。在这种还原NiCl ₂ .6H ₂ O之前，用N ₂进行了反复抽空和吹扫凝胶的新技术。为了代替存在于凝胶孔中的空气，其次，在木船中在N ₂气氛中进行原位还原以产生足够的还原气氛以防止金属Ni的再氧化。通过X射线衍射，动态光散射等不同的表征技术对氧化铝-镍纳米复合材料进行了深入研究。有趣的是，与更高的温度相比，在较高的温度下还原时，可以得到更细颗粒的氧化铝-Ni复合材料。文本中解释了这种现象。