A numerical study of ultraprecision machining of monocrystalline silicon with laser nano-structured diamond tools by atomistic simulation
A numerical study of ultraprecision machining of monocrystalline silicon with laser nano-structured diamond tools by atomistic simulation
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DOI：
10.1016/j.apsusc.2016.10.014
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发表时间：
2017-01-30
影响因子：
6.7
通讯作者：
Fei, Xinjiang
中科院分区：
文献类型：
--
作者：
Dai, Houfu;Chen, Genyu;Fei, Xinjiang
采用三维分子动力学（MD）模拟研究了激光制备的纳米结构金刚石刀具对单晶硅的超精密加工。讨论了采用结构化刀具加工金刚石与采用非结构化刀具加工金刚石的优缺点。研究了纳米加工过程中的von Mises应力分布、静水应力分布、原子位移、应力、径向分布函数、切削力、摩擦系数、亚表面温度和势能。通过分析纳米加工过程中残余应力的分布，建立了亚表面损伤机理的理论分析模型。结果表明，纳米结构刀具在加工脆性材料硅时，产生较小的静水应力、较小的压正应力σ (xx)和σ (yy)，切削温度较低，切削力较小。然而，结构纳米刀具加工导致了更小的芯片体积和更多的-硅相。此外，带有v型沟槽的刀具的摩擦系数小于非结构化刀具和其他结构化纳米刀具。这意味着带有v形槽的刀具在纳米加工过程中可以减少切削阻力。此外，研究结果还指出，金字塔结构工具的亚表面原子势能和其他原子的数量远小于非结构工具和其他结构纳米工具。(C) 2016 Elsevier B.V.版权所有
Three-dimension molecular dynamics (MD) simulations is employed to investigate the ultraprecision machining of single crystal silicon with structured nanoscale diamond tool fabricated by laser. The advantages and disadvantages of diamond machining using structured tools are discussed in comparison with those, of using non-structured tools. The von Mises stress distribution, hydrostatic stress distribution, atomic displacement, stress, the radial distribution function, cutting forces, frictional coefficient, subsurface temperature and potential energy during the nanometric machining process are studied. A theoretical analysis model is also established to investigate the subsurface damage mechanism by analyzing the distribution of residual stress during the nanoscale machining process. The results show that a structured nanoscale tool in machining brittle material silicon causes a smaller hydrostatic stress, a less compressive normal stress sigma(xx), and sigma(yy), a lower temperature and a smaller cutting force. However, the structured nanoscale tool machining results in smaller chip volume and more beta-silicon phase. Besides, the friction coefficient for tool with V-shape groove is smaller than those for non-structured tools and other structured nanoscale tools. This means that the tool with V-shape groove can reduce the resistance to cutting during the nanoscale machining process. In addition, the results also point out that the potential energy of subsurface atoms and the number of other atoms for pyramid-structured tool are much smaller than those of using non-structured tools and other structured nanoscale tools. (C) 2016 Elsevier B.V. All rights reserved.