Laser Assisted Machining of Silicon Nitride (Si₃N₄) Ceramics

Advanced structural ceramics have been increasingly used in automotive, aerospace, military, medical and other applications due to their high temperature strength, low density, thermal and chemical stability, and good wear resistance. Machining is required for a large percentage of the advanced ceramic components made today.  Due to the high hardness and brittleness of ceramic materials, diamond grinding is the most commonly used industrial ceramic machining process.  While good surface quality can be achieved by diamond grinding, the low efficiency in material removal and large wheel wear result in high machining costs. In addition, the subsurface cracks induced by grinding are difficult to detect and lead to material strength degradation.  The goal of this research is to explore laser assisted machining (LAM) as a potential cost-effective industrial ceramic machining process. Both experimental assessment and numerical modeling are used to study the material removal process, tool wear mechanisms, and surface integrity of the machined parts.

• Experimental setup for laser assisted milling

• Heat transfer and thermal stress modeling by finite element analysis (FEA)

                                                Model configuration for laser assisted milling

• Simulation of orthogonal machining of ceramics using distinct element method (DEM)

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Acknowledgements

Financial support of this research from Kansas NSF EPSCoR, NSF, and SME are gratefully acknowledged.