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

在第二个资助期，第一个资助期产生的新型PVD/CVD原位层合板将在性能和加工技术方面进一步发展，并准备在不同的基材上应用。重要的出发点是调整钻石结构，从而调整其残余应力和形貌，以便在减少颗粒和小平面尺寸的基础上提高整体钻石的强度。此外，通过特定的金属夹层厚度和化学成分的调整来实现对金刚石-金属层板界面结合强度的调整。新的金刚石-金属层合板将通过原位三点和四点弯曲和有限元模拟来进行机械特性表征。一个新的焦点是通过4PB剥离测试实现的界面粘附性的量化，其中单层压层被预先损坏。从可能的应用角度出发，研究了一种新型的反应性纳米锡箔低热量自焊原位焊点。基于这些发现，正在考虑直接在层压板上进行自焊纳米PVD夹层的单独处理。基板上的粘合或界面粘合也通过4PB剥离试验来表征，这些剥离试验是通过预先损坏的弯曲梁进行的。然后，将通过洛克韦尔-C压痕和摩擦学测试来表征优化的层压板和焊接的保护效果。最后，利用与铝带拉深模具摩擦学系统相适应的万能摩擦试验机进行了展示研究，以展示与纯金刚石相比，金刚石-金属层合板具有更好的性能潜力。

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.