Optimization of Polyimide Cutting Parameters Based on Finite Element Simulation
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摘要: 采用VUMAT子程序嵌入法,考察了聚酰亚胺高分子材料弹性变形阶段的应力-应变关系,并通过三维热-力耦合有限元模型分析了切削工艺参数对聚酰亚胺铣削过程中切削力、切削温度和切屑形态的影响规律。结果发现:随着进给量的增大,仿真的切削力、切削温度增加或升高,切屑的带状化程度变得严重。随后利用切削实验,验证了仿真模型的有效性与准确性,并获得了聚酰亚胺的最优切削工艺参数:进给量为0.20~0.30 mm/r。Abstract: Using the VUMAT subroutine embedding method, the stress-strain relationship in the elastic deformation stage of the polyimide polymer material is described, and the effects of the cutting process parameters on the cutting force of the polyimide milling process are analyzed through the three-dimensional thermal-mechanical coupling finite element model. The influence law on cutting force, temperature and chip morphology of the polyimide milling process is analyzed through the three-dimensional thermal-mechanical coupling finite element model. The result is that as the feed rate increases, the simulated cutting force and cutting temperature increase as well, and the degree of banding of chips will become serious. Subsequently, the cutting experiment was used, and the cutting force difference between the simulation and experiment was up to 18%, and the cutting temperature difference was up to 23%. When the feed rate increases, the degree of chip curling increases and the surface texture becomes deeper. When the feed rate is 0.15 mm/r and 0.45 mm/r, the chip edge tears. Defects such as adhesion, drawing, and layup of tiny chips on the machined surface of the workpiece cause the material microporous flow channel to be blocked. This constitutive model has certain universality to polymer materials. The validity and accuracy of the simulation model have been verified, and the optimal milling process parameters for polyimide have been obtained: milling depth (ap) is 1 mm, milling speed (v) is 75 m/min, and feed amount f = 0.20~0.30 mm/r.
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Key words:
- polyimide /
- finite element analysis /
- constitutive model /
- milling
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表 1 刀具和工件的物理参数
Table 1. Physical parameters of tool and workpiece
Material ρ/(kg·m−3) E /10−9 Pa ν k/(W·m−1·K−1) α/10−5 K−1 c/(J·kg−1·K−1) Tm/K 303 K 333 K 363 K 323 K 373 K Polyimide 1110 4 3.61 3.12 0.34 0.85(373 K) 5.8 5.7 1250 600 YG8 14500 640 640 640 0.22 75.4 0.45 0.45 220 1 923 表 2 铣刀尺寸参考值
Table 2. Reference value of milling inserts
Material Species Coating D/mm d/mm l/mm L/mm θ/(°) Carbide Flat-end AlTiN 5 6 13 50 45 表 3 铣削仿真参数
Table 3. Milling simulation parameter
Group ap/mm vc/(m·min−1) f/(mm·r−1) 1 1 75 0.10 2 1 75 0.15 3 1 75 0.20 4 1 75 0.25 5 1 75 0.30 6 1 75 0.35 7 1 75 0.40 8 1 75 0.45 -
[1] ZHAO H X, PRIETO L O, ZHOU X Z, et al. Multistimuli responsive liquid‐release in dynamic polymer coatings for controlling surface slipperiness and optical performance[J]. Advanced Materials Interfaces, 2019, 6: 1901028. doi: 10.1002/admi.201901028 [2] JIA W H, YANG S R, REN S L, et al. Preparation and tribological behaviors of porous oil-containing polyimide/ hollow mesoporous silica nanospheres composite films[J]. Tribology International, 2020, 145: 106184. doi: 10.1016/j.triboint.2020.106184 [3] 兰中旭, 韦嘉, 俞燕蕾. 耐高温无色透明聚酰亚胺的研究进展[J]. 功能高分子学报, 2020, 33(4): 320-332. [4] WANG F B, BIN Z, WANG Y Q. Milling force of quartz fiber-reinforced polyimide composite based on cryogenic cooling[J]. The International Journal of Advanced Manufacturing Technology, 2019, 104: 2363-2375. doi: 10.1007/s00170-019-04050-0 [5] 岳彩旭, 蔡春彬, 黄翠, 等. 切削加工过程有限元仿真研究的最新进展[J]. 系统仿真学报, 2016, 28(4): 815-825, 832. [6] 夏晓东, 唐迪, 王业甫, 等. 超精密切削SiCp/Al复合材料有限元仿真研究[J]. 工具技术, 2019, 53(3): 47-50. [7] 秦旭达, 李永行, 王斌, 等. CFRP纤维方向对切削过程影响规律的仿真研究[J]. 机械科学与技术, 2016, 35(3): 472-476. [8] HE Y L, DAVIM J P, XUE H Q. 3D progressive damage based macro-mechanical FE simulation of machining unidirectional FRP composite[J]. Chinese Journal of Mechanical Engineering, 2018, 31(3): 128-143. [9] CHENG H, GAO J Y, KAFKA O L, et al. A micro-scale cutting model for UD CFRP composites with thermo-mechanical coupling[J]. Composite Science and Technology, 2017, 153: 18-31. doi: 10.1016/j.compscitech.2017.09.028 [10] 杨永喜. 聚酰亚胺基多孔含油材料的制备及改性研究[D]. 黑龙江: 哈尔滨工业大学, 2017. [11] 杜茂华, 程正, 王神送, 等. 损伤演化对Ti6Al4V高速切削仿真结果的影响[J]. 航空学报, 2019, 40(7): 279-291. [12] SUHAS B, JACOB B, RYAN S, et al. Constitutive models for the viscoelastic behavior of polyimide membranes at room and deep cryogenic temperatures[J]. Fusion Science and Technology, 2016, 70(2): 332-340. doi: 10.13182/FST15-218 [13] 汪品红. 基于Abaqus子程序的高分子材料本构关系实现[J]. 计算机辅助工程, 2013, 22(S2): 408-410. [14] Zhu Z L, BUCK D, GUO X L, et al. Cutting performance in the helical milling of stone-plastic composite with diamond tools[J]. CIRP Journal of Manufacturing Science and Technology, 2020, 31: 119-129. doi: 10.1016/j.cirpj.2020.10.005 -