Development of high-strength, damage-tolerant CVD-diamond-foil compounds

在第二个资助期内，将进一步开发第一个资助期内产生的新型PVD/CVD原位层压板的性能和工艺技术，并准备应用于不同的基材。重要的出发点是金刚石结构的适应性，从而适应其残余应力和形貌，以便基于晶粒和刻面尺寸的减小来实现单片金刚石强度的增加。此外，金刚石-金属叠层的界面粘合强度的调节通过金属中间层厚度和化学组成的特定调节来实现。新的金刚石-金属层压板将通过原位3点和4点弯曲以及FEM建模进行机械表征。一个新的重点是量化的界面粘合力，实现了4PB剥离测试，其中单层压层是预先损坏。在一个可能的应用方面，研究了一种新型的反应性纳米锡箔的低热自钎焊原位焊点。基于这些发现，正在考虑直接在层压板上单独处理自焊接纳米PVD夹层。基材上的粘附力或界面粘附力也通过使用预损坏弯曲梁的4PB剥离测试来表征。优化层压板和焊接的保护效果将通过洛氏C压痕和摩擦学测试进行表征。最后，一个展示性的研究进行了一个通用的摩擦试验机，以证明更好的性能潜力的金刚石-金属层压板相比，纯金刚石的铝拉丝模在带材拉拔的摩擦系统。

In the second funding period, the novel PVD/CVD in-situ laminates generated in the first funding period will be further developed in terms of their properties and process technology and prepared for application on different substrates. Important starting points are the adaptation of the diamond structure and thus its residual stresses and topography in order to achieve an increase in the strength of monolithic diamond, based on a reduction in the grain and facet size. Furthermore, an adjustment of the interface adhesion strength of the diamond-metal laminates is to be achieved by a specific adjustment of the metallic interlayer thickness and the chemical composition. The new diamond-metal laminates will be mechanically characterised by means of in-situ 3- and 4-point bending and FEM modelling. A new focus is on a quantification of the interfacial adhesion, realised by 4PB peel tests, where single laminate layers are pre-damaged. With regard to a possible application, novel low-heat self-soldering in-situ solder joints with reactive nano-solder foils are investigated. Based on these findings, a separate processing of self-soldering nano-PVD interlayers directly on the laminate is being considered. The adhesion or interfacial adhesion on the substrates is also characterised via 4PB peel tests with pre-damaged bending beams. The protective effect of the optimised laminates and soldering will then be characterised by means of Rockwell-C indentation and tribological tests. Finally, a showcase study is carried out with a universal tribometer adapted to the tribological system of aluminium drawing dies in strip drawing in order to demonstrate the better performance potential of diamond-metal laminates compared to pure diamond.