【作者】 张欢；

【导师】 曲彦平； 韩亚苓；

【作者基本信息】 沈阳工业大学 ， 材料学， 2007， 硕士

【摘要】 对纳米氧化铝粉体进行化学镀Ni-P合金，不仅可以降低粉体颗粒间的团聚几率、提高粉体的表面活性，而且还可以综合基体粉体（氧化铝）与金属镀层（Ni-P合金）各自的优点，进而拓展一些新的功能。鉴于以上目的，本文研究了纳米粉体化学镀的前处理工艺和化学镀工艺，并优化出了最佳的前处理工艺、镀液配方及施镀方案。同时进行了镀液的寿命实验，通过对镀液中Ni²⁺的定期检测，计算出溶液中NiSO₄的含量，并制定出了相应的补加方案。利用寿命实验测出镀液的使用周期，为复合粉体的生产化提供了有利的前提。在此基础上，对已施镀的氧化铝黑色粉末进行X射线衍射及扫描电镜检测，结果表明，氧化铝粉末施镀完全，镀层含镍量为9.32％，含磷量为2.32％，镀层呈晶体态结构。采用化学镀的方法将金属镍包覆在氧化铝粉体表面，可以避免传统球磨法所导致的粉体混合不均匀的问题。通过在粉体表面加入少量金属进行界面改性，可以改善单一颗粒增韧的强韧化效果，实现复合增韧。本文采用无压烧结工艺制备了镍磷合金镀层包覆氧化铝颗粒的特种陶瓷材料。主要研究内容如下：采用镀层中含镍量为9.32％，含磷量为2.32％的包覆型氧化铝颗粒进行了1150～1400℃的无压烧结实验研究，对比了不同烧结工艺下制得的样品情况，得到了最佳工艺：烧结温度为1350℃、保温时间40 min。并检测了样品的断裂韧性、致密度、耐磨性。与单一氧化铝陶瓷对比，断裂韧性从单一Al₂O₃陶瓷的3.0 MPa·m^1/2提高到6.91MPa·m^1/2，增加了130.3％；致密度最高可达到96.8％；耐磨性良好。更多还原

【Abstract】 Electroless Ni-P alloy plating on the nano alumina powder not only improves the weakness of the nano Alumina powder, which easily reunites, and enhances the powder’s face activity, but also may combines the respective merit of substrate powder（Alumina） and metallic powder（Ni-P alloy）, what is more, may develops some new traits. According to these purposes, during the electroless plating on the nano Alumina power, the paper mainly researches the craft of the former disposal, the basic formulation of the electroless nickel bath and idiographic scheme of electroless Ni-P alloy plating, sequentially elicit optimal the craft of the former disposal, the basic formulation of the electroless nickel bath and idiographic scheme of electroless Ni-P alloy plating. At the same time, the life span of the EN solution is also studied by a series of experiments, which firstly analyses the content of Ni²⁺by titration , secondly calculating the content of NiSO₄ by formula and accordingly constituting appropriate addition scheme. Making use of the experiments of the life span of the EN solution may ascertain the metal turn over （MTO） of the EN solution, the aim of experiments is a batch production of the powder. On this ground work, the black nano Alumina powder which is plated steer the diffraction of X ray and Scan the electric mirror examination analysis, As a result, the alumina dust is fully plated ,the plated lay includes the nickel as 9.32%, phosphorus as 2.32%, which present the crystal structure.Coating surfaces of Al₂O₃ powder by electroless method is believed to be an effective way to prevent powders from amalgamating and growing, avoiding heterogeneous distribution of low content additive when using conventional ball-milling method, to achieve synergistic toughening by interfacial modification.In this paper, with Ni-P coated Al₂O₃ powder as staring powders, sintered composites was obtained by non-pressing the mixture of powder. The mail contents are as follows: Non-pressing were carried out in the range of 1150℃to 1400℃with Ni content 9.32% and phosphorus content 2.32%. For comparison, the processing parameters of Al₂O₃/ Ni-P special ceramics were further optimized to be 1350℃and 40 min. Then the sample’s properties were tested which included break flexibility density and abrasion. In comparison with Al₂O₃ composites, the break flexibility was improved from 3.0 MPa·m^1/2 to 6.91 MPa·m^1/2 by 130.3%; the highest density was 96.8%; the abrasion was ameliorated.更多还原