Material removal mechanisms in grinding of fiber-reinforced non-oxide ceramics

点击翻译按钮获取中文摘要

Due to a limited development potential in terms of thermal resistance of metallic superalloys, fiber-reinforced ceramics came into the focus of material developments. The grinding behavior and the material removal mechanisms in grinding of ceramics were analyzed for monolithic ceramics. It has been shown in several scientific works, that ductile grinding of brittle materials is possible. Although investigations regarding the grinding behavior of fiber-reinforced ceramics (ceramic matrix composites (CMCs)) were already published, the underlying material removal mechanisms are largely unknown. Also, the influence of a grinding process on the surface zone is only investigated sporadically. For an optimized process design, systematic tests considering the material removal mechanisms as well as a deep material understanding is necessary.The goal of the project is to develop a heuristic model for the material removal mechanisms in grinding fiber-reinforced non-oxide ceramics. Using the example of C/SiC and SiC/SiC ceramics, the influence of the fiber orientation and the fiber material on the machining characteristics will be described both, qualitatively and quantitatively. Furthermore, it will be explained, which cause-effect relationships between the grinding parameters and the resulting surface integrity zone exist and to what extent the effects of a grinding process can be influenced by the fiber orientation and fiber material. An empirical model will be developed, which describes the material removal mechanisms as a function of the material properties and the grinding process parameters. Based on the findings, a heuristic model will be derived, which explains the material removal mechanisms and the surface integrity zone properties of the workpiece after grinding on basis of the material properties.