High Performance Polymer Composites for Tribosystems in Hydrogen Environment

拟议研究项目的目的是测试基于聚醚醚酮（PEEK）和聚酰亚胺（PI）的聚合物复合材料在气态和液态氢摩擦系统中的适用性。由于其优异的机械性能，PEEK可用于摩擦应力部件，并已在许多应用中用作金属材料的替代品。与PEEK相比，PI适用于更宽的温度范围，因此，它将被纳入研究范围。作为固体润滑剂，各种含量的天然或合成石墨将被混合到聚合物中。在项目的后期阶段，计划通过添加碳纳米管和/或纳米颗粒来优化材料。由于含氢元件偶尔会暴露在空气中，并且出于安全原因，必须在进气口之前进行惰性化，因此在空气和惰性气体（如氮气）中也具有可靠的功能，属于对摩擦应力元件的要求。因此，还将在空气中进行试验，并在真空环境中代替惰性环境进行试验。摩擦和磨损数据将通过与轴承钢和奥氏体不锈钢滑动摩擦的模型试验配置来获得。聚合物和石墨的摩擦行为受环境介质的影响很大。因此，将特别关注不同环境间摩擦机理的变化以及氢环境下的摩擦化学反应。为此，将研究摩擦表面的形貌和化学成分，如果适用的话，还将研究转移膜。此外，还考虑到对H2气体纯度要求高的应用，将研究脱气行为和磨损碎屑的产生。在某些情况下，反应性磨损碎片甚至可以作为点火源。

Aim of the proposed research project is testing of polymer composite materials based on polyether ether ketone (PEEK) and polyimide (PI) for their suitability for tribosystems running in gaseous and liquid hydrogen. Because of its outstanding mechanical properties PEEK is to be used for frictionally stressed components and is already employed as a replacement for metallic materials in many applications. Compared to PEEK, PI is applicable in a wider temperature range and therefore, it will be included into the investigations. As solid lubricant various contents of natural or synthetic graphite will be admixed to the polymers. In a later phase of the project optimization of the materials by addition of carbon nanotubes and/or nanoparticles planned. Because hydrogen containing components are occasionally exposed to air and, because of safety reasons, have to be inertised before air inlet, a reliable function also in air and inert gases such as nitrogen belong to the requirements for frictionally stressed components. Therefore, also tests in air and, substitutional for inert environment, in vacuum will be carried out.The friction and wear data will be obtained by means of model test configurations in sliding friction against bearing steel and austenitic stainless steel. The frictional behavior of the polymers and also of graphite is considerably influenced by the environmental medium. Therefore, special attention will be paid to changes of friction mechanisms between different environments and tribochemical reactions in hydrogen environment. For this purpose, the topography and chemical composition of the friction surfaces and, if applicable, the transfer films will be investigated. Furthermore, also in view of applications with high purity requirements for the H2 gas, the outgasing behavior and creation of wear debris will be investigated. Under certain circumstances, reactive wear debris may even act as an ignition source.