Theory of chip formation in grinding of fiber reinforced ceramics with porous matrix

• Applicant: Professor Dr.-Ing. Thomas Bergs, since 7/2019
• Subject Area: Metal-Cutting and Abrasive Manufacturing Engineering
• Term: from 2017 to 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 374031440

The demand for lightweight construction leads to innovative material applications, as well as a constant development of construction materials. Due to a limited development potential in terms of thermal resistance of metallic superalloys, fiber-reinforced ceramics came into the focus of material developments. Fiber-reinforced ceramics (ceramic matrix composites (CMCs)) represent a group of materials with high application potential and future importance due to their high mechanical stability, high damage tolerance and thermal resistance a well as low density. Fiber-reinforced ceramics with porous matrix represent a modern design concept, which can be produced at lower costs in comparison to conventional fiber-reinforced ceramics with dense matrix. However, the machining characteristics of fiber-reinforced ceramics with porous matrix are not investigated yet. Thus, it is not known to what extent a grinding process affects the peripheral zone of these materials.The goal of the project is to develop an explanatory model for the cutting mechanisms in grinding fiber-reinforced oxide ceramics with porous matrix and thereby enable an optimized knowledge-based grinding process design. Using the example of WHIPOX ceramics, in which both the matrix and the fibers consist of an oxide ceramic, 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 chip formation 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 cutting mechanisms and the surface integrity zone properties of the workpiece after grinding on basis of the material properties.

• DFG Programme: Research Grants
• Ehemaliger Antragsteller: Professor Dr.-Ing. Fritz Klocke, until 6/2019