Ternary Ru/Al-based reactive multilayers

三元Ru/Al基反应性多层膜

基本信息

批准号：
258672203
负责人：
Professor Dr.-Ing. Alfred Ludwig
金额：
--
依托单位：
Lehrstuhl für Funktionswerkstoffe
依托单位国家：
德国
项目类别：
Research Grants
财政年份：
2014
资助国家：
德国
起止时间：
2013-12-31 至 2016-12-31
项目状态：
已结题

来源：
https://gepris.dfg.de/gepris/projekt/258672203?language=en
关键词：
Ternary Ru Al based reactive

项目摘要

The intermetallic B2 compound RuAl combines good high-temperature properties with high room-temperature ductility. The high negative heat of formation of -62 kJ/mol(atoms) enables sub-µm composites of Ru and Al to self-propagating exothermic reactions forming the B2 compound RuAl. This makes the system Ru/Al similar to other intermetallic reactive systems like Ni/Al, Pt/Al, Pd/Al and Co/Al. However, the system Ru/Al is of particular interest due to the combination of a ductile reaction product, a compositional range of existence of 4.1 % at. (at room temperature) and a good energy density (comparable to that of commercially available Ni/Al foils). This makes Ru/Al an interesting system in the field of reactive bonding with local heating limited to the region of joining. The characteristic parameter of binary reactive multilayer systems is the bilayer thickness by which the basic properties of the system (speed of reaction, ignition temperature, microstructure and morphology of the reaction product) are determined and cannot be varied independently. Aim of this project is to develop a new way to manipulate the properties of Ru/Al-based reactive multilayers by moving from binary to ternary Ru/Al/X layers (X=Ni, Pt, Hf, Ti). The focus is on lowering the relatively high ignition temperature of Ru/Al multilayers (400-575°C) to values of approximately 300°C, comparable to that of Ni/Al multilayers, thus improving the reaction in the presence of a heat sink (e.g. inside a joint gap). Because there are, to the best knowledge of the applicants, no systematic studies on ternary intermetallic reactive systems, an essential part of this project is to investigate the influence of chemical composition and stacking sequence on the basic properties of a reactive multilayer (speed of reaction, morphology and microstructure). Thereby, a better understanding of the underlying mechanisms shall be gained. To enable the investigation of large ranges of composition, combinatorial sputtering is employed. This technique allows deposition of materials libraries on a single substrate by sequential sputtering of layers with thickness gradients. The compositional range of existence of the RuAl-based B2 structure is investigated by X-ray diffraction and high-throughput electrical resistivity measurements after a thermal treatment of the ternary multilayers. Within these compositional ranges, intermetallic phase formation as a function of temperature is investigated by in-situ four point measurements of the electrical resistivity to draw conclusions on the ignition temperature. Based on the insights into the influence of composition and stacking sequence, ternary Ru/Al based reactive multilayers are developed combining the benefits of Ru/Al with a reduced ignition temperature.

金属间的B2复合rual结合了良好的高温特性和高房间温度的延展性。 -62 kJ/mol（原子）形成的高负热使Ru和Al的亚µm组成产生了形成B2化合物Rual的自发放热反应。这使该系统类似于其他金属间反应系统，例如Ni/Al，pt/al，pd/al and co/al。但是，由于延性反应产物的组合，该系统特别感兴趣，这是4.1％的复合范围。（在室温下）和良好的能量密度（与市售的Ni/Al Foils相当）。这使Ru/Al成为反应性键合的有趣系统，局部加热限于连接区域。二进制反应性多层系统的特征参数是双层厚度，该系统的基本特性（反应速度，点火温度，微结构和反应产物的形态）是确定的，并且不能独立变化。该项目的目的是开发一种新的方法来通过从二进制到三元ru/al/x层（x = ni，pt，hf，ti）来操纵基于RU/AL的反应性多层。重点是降低Ru/Al多层的相对高点火温度（400-575°C），可与大约300°C的值，与Ni/Al多层相当，从而在存在散热器的情况下改善反应（例如，在关节间隙内部）。据最佳了解应用，没有关于三元金属间反应性系统的系统研究，因此该项目的重要组成部分是研究化学组成和堆叠序列对反应性多层的基本特性的影响（反应，形态和微结构的速度）。因此，应获得对基本机制的更好理解。为了实现大量构图的投资，采用了组合溅射。该技术允许通过对厚度梯度的层进行顺序溅射来将材料库在单个基材上沉积。基于Rual的B2结构的存在的组成范围是通过X射线衍射和三元多层热处理后的高通量电阻测量来投资的。在这些组成范围内，金属间的形成随温度的函数通过电阻的四点测量来投入，以得出点火温度的结论。基于对组成和堆叠序列影响的见解，基于三元/Al的反应性多层是将Ru/Al的好处与降低点火温度相结合的。