Numerical simulation of material-oriented ultra-precision diamond polishing: overview and prospects

Publish in the International extreme production magazine researchers from Harbin Institute of Technology, Huazhong University of Science and Technology, Guizhou University and Ruhr-University Bochum present a brief overview of the application of numerical simulations in addressing the impact of properties and microstructures of workpiece materials on the diamond polishing mechanisms of various kinds of workpiece materials, such as metal, hard brittle materials and composite materials.

In addition, the effect of applying an external energy field to the diamond grinding of materials that are difficult to machine is also discussed.

The anisotropic deformation behavior between single crystal grains in the diamond polishing of polycrystalline materials can be well described at the microscopic scale through crystal plasticity finite element simulation, providing a basis for the fundamental understanding of formation mechanisms and for suppressing the strategy of grain boundary surface steps on the machined surface .

The variation of the tool-chip frictional state with the cutting temperature can be effectively captured by the thermos-mechanical clutch-adhesive friction criterion embedded in the finite element model. In addition, the wear of the diamond tool can be suppressed by applying textures to the cutting tool.

The fundamental understanding of phase transformation and cracking events through simulations is crucial for revealing the brittle-to-ductile transition mechanisms of hard brittle materials, enabling the rational selection of optimized parameters for improved ductile machinability.

The physics-based numerical model is critical for delivering predicted results that are in agreement with experimental data for composite materials. The real microstructural features of the enhanced phase and proper handling of the enhanced phase-matrix interface are essentially necessary to accurately represent the tool phase interactions in numerical simulations of diamond grinding of composites.

The configuration of external fields (vibration field, thermal field, and ion implantation field) and their interactions with workpiece material without loss of physics is critical for revealing the mechanisms of field-assisted diamond grinding of difficult-to-machine materials with improved machinability through numerical simulations.

One of the principal investigators, Professor Junjie Zhang, commented: “For atomic and near-atomic scale fabrication, which deals with the processing of atomic-scale materials with pronounced effect on surface size, ultra-precision diamond grinding also plays an important role for its achievable sub-nanometer machining accuracy.”

“The multi-scale numerical simulation, such as microscopic-scale finite element simulation and nanoscale molecular dynamics simulation, have become more popular for their ability to provide dynamic insights into ongoing diamond polishing processes of a variety of materials, such as material deformation, chip formation, cutting force evolution and surface formation.”

First author Dr. Liang Zhao commented, “Despite the wide applications of various simulation methods used in the exploration of the diamond polishing process, there are still issues or challenges to be addressed for better comparison of predicted results with experimental data.”

“In the present work, we present a compact overview of the recent advances in advanced numerical simulations of diamond polishing of a variety of materials, differing in properties, microstructures and constituents. The aspects reported in this work provide guidance for the numerical simulations. of ultra-precise machining reactions for a variety of materials.”

prof. Alexander Hartmaier, director of the Interdisciplinary Center for Simulation of Advanced Materials at Ruhr-Universität Bochum said: “Future research on the numerical simulations of material-oriented diamond polishing can be further recommended from the development of the high-precision physics-based finite model. , primarily aimed at increasing the prediction accuracy of simulation results for advanced structured materials compared to experimental data.”