Simulation and experimental study on micro-cutting silicon carbide crystal with single grain diamond
-
摘要: 为改善碳化硅晶体在微切削过程中的脆性断裂和边缘崩碎问题,建立了金刚石锥形磨粒微切削碳化硅工件的有限元模型,首先通过前置仿真模型确定了微切削深度和速度的选择范围。随后采用正交试验法对影响切削力的主要因素和次要因素进行了分析,又研究了单一切削参数对切削效果的影响。最后借助赫兹接触理论,分析了金刚石探针加载力对摩擦力和切削表面形貌的影响。结果表明:切削深度在1.5μm以下时切削质量较好。切削深度B是影响切削力的显著因素,切削速度C和磨料切削刃角度A是非显著因素,切削参数优方案为B1C1A2(切削深度0.5μm,切削速度76m/s,磨料切削刃角度60°)。通过控制切削深度可以提高切削稳定性,适当提高切削速度可以在保证切削质量的前提下提高切削效率。金刚石探针压入工件的深度影响与摩擦系数、摩擦力和切削力呈正比,在此压入深度范围下切削边缘的三维轮廓相对平整、光滑。Abstract: In order to improve the brittle fracture and edge breakage of silicon carbide crystal in the micro-cutting process, a finite element simulation model of micro-cutting silicon carbide workpiece with diamond conical abrasive grain was established, and the selection range of micro-cutting depth and speed is determined through the pre-simulation model. Then the orthogonal experiment method is used to analyze the primary and secondary factors on the cutting force. Subsequently, the influence of single micro-cutting parameter on cutting effect is studied. Finally, with the help of Hertzian contact stress, the cutting force and quality of cutting edge were analyzed by scratching the silicon carbide crystal with a diamond tip. The maximum cutting depth is determined to be 1.5 μm by pre-simulation model. The cutting depth B is a significant factor affecting the main cutting force, cutting speed C and conical angle of diamond grain A are non-significant factors, and the optimal scheme of cutting parameters is B1C1A2 (cutting depth 0.5 μm, cutting speed 76 m/s, conical angle of diamond grain 60°). It can improve the cutting stability by controlling the cutting depth, and appropriately improve the cutting speed can improve the cutting efficiency and ensure the cutting quality. The depth of pressing into the workpiece of diamond tip affects the friction coefficient, friction force and cutting force, and the 3D profiles of cutting edges are relatively clear, straight and clean.
-
Key words:
- silicon carbide crystal /
- diamond grain /
- diamond tip /
- cutting force /
- cutting edge quality
点击查看大图
计量
- 文章访问数: 254
- HTML全文浏览量: 86
- 被引次数: 0