Kang Qiang, Kong Xianguang, Chang Jiantao, Fang Xudong, Kang Chengwei, Wu Chen, Li Changsheng, Maeda Ryutaro, Jiang Zhuangde
School of Mechano-Electronic Engineering, Xidian University, State Key Laboratory of Electromechanical Integrated Manufacturing of High-perfommance Electronic Equipments, Xidian University, Xi'an 710071, People's Republic of China.
State Key Laboratory for Manufacturing Systems Engineering, International Joint Laboratory for Micro/Nano Manufacturing and Measurement Technologies, Xi'an Jiaotong University, School of Mechanical Engineering, Xi'an Jiaotong University, Xi'an 710049, People's Republic of China.
Nanotechnology. 2024 Jun 4;35(34). doi: 10.1088/1361-6528/ad3b00.
This study utilized ion implantation to modify the material properties of silicon carbide (SiC) to mitigate subsurface damage during SiC machining. The paper analyzed the mechanism of hydrogen ion implantation on the machining performance of SiC at the atomic scale. A molecular dynamics model of nanoscale cutting of an ion-implanted SiC workpiece using a non-rigid regular tetrakaidecahedral diamond abrasive grain was established. The study investigated the effects of ion implantation on crystal structure phase transformation, dislocation nucleation, and defect structure evolution. Results showed ion implantation modification decreased the extension depth of amorphous structures in the subsurface layer, thereby enhancing the surface and subsurface integrity of the SiC workpiece. Additionally, dislocation extension length and volume within the lattice structure were lower in the ion-implanted workpiece compared to non-implanted ones. Phase transformation, compressive pressure, and cutting stress of the lattice in the shear region per unit volume were lower in the ion-implanted workpiece than the non-implanted one. Taking the diamond abrasive grain as the research subject, the mechanism of grain wear under ion implantation was explored. Grain expansion, compression, and atomic volumetric strain wear rate were higher in the non-implanted workpiece versus implanted ones. Under shear extrusion of the SiC workpiece, dangling bonds of atoms in the diamond grain were unstable, resulting in graphitization of the diamond structure at elevated temperatures. This study established a solid theoretical and practical foundation for realizing non-destructive machining at the atomic scale, encompassing both theoretical principles and practical applications.
本研究利用离子注入来改变碳化硅（SiC）的材料性能，以减轻SiC加工过程中的亚表面损伤。本文在原子尺度上分析了氢离子注入对SiC加工性能的影响机制。建立了使用非刚性正十四面体金刚石磨粒对离子注入后的SiC工件进行纳米级切削的分子动力学模型。该研究调查了离子注入对晶体结构相变、位错形核和缺陷结构演变的影响。结果表明，离子注入改性降低了亚表层非晶结构的扩展深度，从而提高了SiC工件的表面和亚表面完整性。此外，与未注入离子的工件相比，注入离子的工件晶格结构中位错的延伸长度和体积更小。注入离子的工件每单位体积剪切区域内晶格的相变、压缩压力和切削应力均低于未注入离子的工件。以金刚石磨粒为研究对象，探索了离子注入条件下的磨粒磨损机制。未注入离子的工件相比注入离子的工件，磨粒的膨胀、压缩和原子体积应变磨损率更高。在SiC工件的剪切挤压作用下，金刚石磨粒中原子的悬空键不稳定，导致金刚石结构在高温下石墨化。本研究为实现原子尺度的无损加工奠定了坚实的理论和实践基础，涵盖了理论原理和实际应用。
