Coating materials made of high-entropy alloys for tribologically highly stressed surfaces

除了经典材料概念的进一步发展外，不含主导合金元素的新型合金系统为涂层系统的优异性能提供了一个有前途的、科学相关的研究领域，有望应用于高应力表面。该项目的总体目标是研究高熵合金的工艺-显微组织-性能关系，以开发摩擦学高应力表面的热喷涂涂层。关于通过热喷涂实现所描述的材料概念，高熵合金内部的化学成分和均匀分布要求是一个巨大的科学和技术挑战。雾化粉末冶金生产似乎适合满足这些要求，并为高速氧燃料热喷涂工艺的特定加工条件提供量身定制的原料。考虑化学和结构参数的工艺时间制度的确定需要在项目中必须调查的工艺-材料相互作用的基础上采用整体开发方法。热喷涂涂层、铸锭和火花等离子烧结样品的特性有助于将粉末冶金生产的材料与铸造工艺路线进行比较，特别是在热和大气工艺条件方面。因此，可以全面了解结构参数对表面性能的影响，从而为表面涂层技术领域的应用奠定材料科学相关的基础。

Beside the further development of classic material concepts, novel alloy systems without a dominating main alloying element offer a promising, scientifically relevant research field with regard to excellent properties of coating systems which are expected to be applicable for highly stressed surfaces. The overarching goal of the proposed project is the investigation of process-microstructure-property relations of high-entropy alloys for the development of thermally sprayed coatings on tribologically highly stressed surfaces. As regards the implementation of the described material concept by means of thermal spraying, the requirements with respect to the chemical composition and homogeneous distribution within the high-entropy alloy represent a great scientific and technical challenge. The powder metallurgical production by atomization appears appropriate to meet these requirements and to provide a feedstock material which is tailor-made for the specific processing conditions of the high-velocity oxygen fuel thermal spray process. The determination of the process time regime considering chemical and structural parameters requires a holistic development approach on the basis of process-material interactions which have to be investigated in the project. The characterization of thermally sprayed coatings, cast ingots and spark plasma-sintered samples facilitates a comparison of the powder metallurgically produced material with the casting process route, especially regarding thermal and atmospheric process conditions. Hence, a comprehensive understanding of the influence of structural parameters as regards surface properties can be gained, therefore establishing a materials science-related basis for applications in the field of surface coating technologies.