赵仲林,安立宝,张好强,董树亮,郭毅.TC4铣削切屑形态与表面形貌特征[J].表面技术,2023,52(5):247-256.
ZHAO Zhong-lin,AN Li-bao,ZHANG Hao-qiang,DONG Shu-liang,GUO Yi.Characteristics of Chip Morphology and Surface Topography in Milling TC4[J].Surface Technology,2023,52(5):247-256 |
| TC4铣削切屑形态与表面形貌特征 |
| Characteristics of Chip Morphology and Surface Topography in Milling TC4 |
| |
| DOI：10.16490/j.cnki.issn.1001-3660.2023.05.024 |
| 中文关键词: TC4 有限元模拟 铣削试验 切屑形态 锯齿状切屑 表面形貌 |
| 英文关键词:TC4 finite element simulation milling experiment chip morphology serrated chips surface morphology |
| 基金项目:河北省自然科学基金(E2021209026) |
|
|
| Author | Institution |
| ZHAO Zhong-lin | College of Mechanical Engineering, North China University of Science and Technology, Hebei Tangshan 063210, China;Beijing Long March Tianmin High-Tech Co., Ltd., Beijing 100176, China |
| AN Li-bao | College of Mechanical Engineering, North China University of Science and Technology, Hebei Tangshan 063210, China |
| ZHANG Hao-qiang | College of Mechanical Engineering, North China University of Science and Technology, Hebei Tangshan 063210, China |
| DONG Shu-liang | College of Mechanical Engineering, North China University of Science and Technology, Hebei Tangshan 063210, China |
| GUO Yi | College of Mechanical Engineering, North China University of Science and Technology, Hebei Tangshan 063210, China |
|
| 摘要点击次数: |
| 全文下载次数: |
| 中文摘要: |
| 目的 对TC4铣削过程中锯齿状切屑的形成与对应产生的加工表面形貌特征进行研究，掌握钛合金TC4高速铣削加工切屑形态随铣削速度的变化规律，从而提高加工表面质量和效率。方法 基于有限元软件，建立钛合金TC4二维变厚度切削模型，通过仿真和铣削试验分析铣削速度对切屑形态的影响规律。利用超景深显微镜和PS50表面轮廓仪对TC4铣削过程中形成的切屑形态及工件加工表面形貌进行观测和分析，确定铣削加工TC4过程中铣削速度与切屑形态、工件表面形貌和表面粗糙度之间的关系。结果 铣削试验验证得出铣削力仿真值与试验值最大误差为9.86%，验证了二维变厚度切削模型的准确性。随着铣削速度从40 m/min增大到120 m/min，切屑形态由带状转变为锯齿状，且铣削力逐渐减小。同时，铣削速度由80 m/min增大到240 m/min时，切屑的锯齿化系数和剪切带内的剪切角均增大，而剪切带间距减小，TC4加工表面波纹加深、波纹间距变宽，并且伴随有大量韧窝出现，导致表面粗糙度值增大。结论 掌握锯齿状切屑几何特征与工件表面形貌随铣削速度的变化规律，以便在铣削加工TC4过程中对锯齿状切屑进行控制，对于提高工件加工表面质量和加工效率具有重要的指导意义。 |
| 英文摘要: |
| Titanium alloy TC4 is widely used in aerospace and other fields due to its high strength-to-weight ratio and excellent corrosion resistance. TC4 has high chemical activity and low thermal conductivity. Unfortunately this results in low processing efficiency and poor surface quality of workpiece. In order to obtain the variation of chip morphology with cutting speed in high-speed milling titanium alloy TC4, and thus to improve the machined surface quality and cutting efficiency, the formation of the serrated chips and the characteristic of the corresponding surface topography in milling TC4 were investigated. In this paper, the finite element software was used to reasonably simplify the milling process of TC4 with YG8 carbide tools, and a two-dimensional variable-thickness cutting model was established to reduce the computational cost and facilitate the observation of microscopic chip morphology. The post-processing results of the model were combined with the TC4 milling experiment to measure the error between the simulation and experiment values of the milling force during the milling process. The effect of the milling speed on the chip morphology was obtained. With milling speedof 120 m/min as an example, the Mises stress, equivalent plastic strain and milling temperature during the three-stage formation of serrated segments were simulated and analyzed. The geometric characterization of the serrated chips was defined through the serration coefficient, the shear angle, and the shear band spacing. The relationship between the milling speed and these characterization variables was studied. Extended depth-of-field microscope and PS50 surface profiler were used to observe and analyze the chip morphology and surface topography formed during TC4 milling, and to determine the relations between the milling speed and chip morphology/workpiece surface topography/surface roughness during milling. The results showed that the maximum error between the simulation and experiment values of the milling force was 9.86%, which verified the accuracy of the 2D variable-thickness cutting model. As the milling speed increased from 40 m/min to 120 m/min, the chip morphology changed from strip to the serrated, and the milling force gradually decreased. 80 m/min was the critical milling speed for serrated chips. The simulation results showed that with the generation of serrated segments, the Mises stress at the first deformation zone gradually decreased, and the equivalent plastic strain value near the middle of the two shear bands also decreased gradually. Meanwhile, the milling temperature in the first deformation zone increased firstly and then decreased. When the milling speed increased from 80 m/min to 240 m/min, the chip serration coefficient and the shear angle both increased, while the shear band spacing decreased. Accompanied by the appearance of a large number of dimples, the surface roughness value increased. When the milling speed was 200 m/min, the increase of the surface roughness value was relatively slow, and the milling efficiency of TC4 was becoming higher. Knowing the change law of the geometric characteristics of serrated chips and surface topography of the workpiece with the milling speed so as to control the serrated chips, is of great guiding significance for improving the surface quality and machining efficiency in TC4 milling process. |
| 查看全文 查看/发表评论 下载PDF阅读器 |
| 关闭 |
|
|
|
渝公网安备 50010702501715号