基于非晶合金的微纳结构热塑性成型制备与表征

发布时间：2018-02-28 16:18

本文关键词： 非晶合金模压热塑性成型脱合金微纳结构　出处：《清华大学》2015年博士论文　论文类型：学位论文

【摘要】：金属微纳结构在催化、传感、检测和光学器件等领域具有广阔的应用前景。非晶合金因具有优异的热塑性成型能力和结构均匀特性,非常适宜于作为制备金属微纳结构的前驱材料。但现有的成型技术难以获得均匀的、大面积非晶合金微纳米结构。因此研究新的非晶合金微纳米结构成型方法,研究新型成型性能优异的非晶合金和扩展非晶合金微纳结构的应用领域具有重要意义。本文在实验研究的基础上提出了非晶合金模压热塑性成型方法,开发出非晶合金模压热塑性成型技术工艺。ANSYS定性模拟仿真结果和实验研究结果均表明,非晶合金模压热塑性成型技术能够消除传统自由压印热塑性成型中存在的压印热塑性成型后微结构不均匀的缺陷,制备出面积大、均匀性好的非晶合金微纳结构。与此同时,在前人的基础上得到了模压热塑性成型过程中的动力学充型公式,该公式预测结果与实验结果相吻合。采用开发的模压热塑性成型工艺,制备出了面积大、尺寸均匀的Pd40.5Ni40.5P19非晶态及晶态纳米线阵列,阵列中纳米线直径约为55 nm,长度可调。揭示了模压热塑性成型参数对纳米线阵列形貌和结构的影响规律以及纳米线晶化机制,实现了纳米线形貌和结构的可控制备。发现提高成型温度、成型压力和增加成型时间可增加纳米线长度。将制备的聚集型Pd40.5Ni40.5P19非晶合金纳米线阵列具有强的表面拉曼增强效应,同时获得了较大的增强因子和很好的空间重复性,为制备高空间重复性的表面拉曼增强基底提供了新的思路。研发出成本低、非晶形成能力大、热塑性成型能力优异和综合力学性能好的Ni62Pd19Si2P17非晶合金,其临界尺寸达11 mm以上。模压热塑性成型制备的Ni62Pd19Si2P17复杂微米结构具有成型精度高的特征,并可作为模具热压印成型制备有机玻璃等塑料和冷压印成型制备纯铜、纯铝和不锈钢等金属的复杂微米结构。Ni62Pd19Si2P17非晶合金可通过电化学脱合金获得表面纳米多孔结构,Zr48Cu36Ag8Al8非晶合金薄带和Zr-Cu-Ag-Al-O非晶态/晶态复合材料薄带可通过化学脱合金方法制备得到多种形态和结构的纳米多孔结构。通过将模压热塑性成型技术和脱合金方法相结合,制备出了基于Ni62Pd19Si2P17和Zr48Cu36Ag8Al8非晶合金的微纳米复合结构。
[Abstract]:Metal nanostructures have broad application prospects in the fields of catalysis, sensing, detection and optical devices. Amorphous alloys have excellent thermoplastic forming ability and uniform structure. It is very suitable to be used as the precursor material for the preparation of metal micro-nano structure. However, the existing molding technology is difficult to obtain uniform, large-area amorphous alloy micro-nano structure. Therefore, a new forming method of amorphous alloy micro-nano structure is studied. It is of great significance to study the application fields of new amorphous alloys and extended amorphous alloys with excellent forming properties. Based on the experimental study, a method of moulded thermoplastic forming of amorphous alloys is proposed. The process of moulding thermoplastic forming of amorphous alloy is developed. The qualitative simulation results and experimental results of ANSYS show that, The immolded thermoplastic forming technology of amorphous alloy can eliminate the defects of non-uniform microstructure in traditional free imprint thermoplastic forming, and produce amorphous alloy micro-nano structure with large area and good homogeneity, at the same time, On the basis of the former, the dynamic filling formula in the process of moulding thermoplastic forming is obtained, and the prediction results are in agreement with the experimental results. A large area has been prepared by using the developed moulding thermoplastic forming technology. The Pd40.5Ni40.5P19 amorphous and crystalline nanowire arrays with uniform size are about 55nm in diameter and adjustable in length. The effect of molding parameters on the morphology and structure of nanowire arrays and the crystallization mechanism of nanowires are revealed. It is found that the length of nanowires can be increased by increasing the molding temperature, forming pressure and forming time. The synthesized Pd40.5Ni40.5P19 amorphous alloy nanowire arrays have strong surface Raman enhancement effect. At the same time, large enhancement factors and good spatial repeatability are obtained, which provides a new idea for the preparation of surface-Raman enhanced substrates with high spatial repeatability. The critical size of Ni62Pd19Si2P17 amorphous alloy with excellent thermoplastic forming ability and good comprehensive mechanical properties is more than 11 mm. The complex micron structure of Ni62Pd19Si2P17 prepared by thermoplastic molding has the characteristics of high forming precision. And can be used as mould hot stamping to prepare plastic such as plexiglass and cold stamping to prepare pure copper. Complex micron structure of pure aluminum and stainless steel. Ni62Pd19Si2P17 amorphous alloy can be chemically dealloyed by electrochemical dealloying of nano-porous Zr48Cu36Ag8Al8 amorphous alloy strip and Zr-Cu-Ag-Al-O amorphous / crystalline composite strip. Nano-porous structures with various shapes and structures were prepared by the method. The thermoplastic molding technology was combined with the dealloying method. Micro and nano composite structures based on Ni62Pd19Si2P17 and Zr48Cu36Ag8Al8 amorphous alloys were prepared.
【学位授予单位】：清华大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：TG139.8

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