Microscale parts made of Polyether-Ether-Ketone (PEEK) are widely used in biomedical, aerospace, and manufacturing industries. The formation mechanism of the chip and machining quality of PEEK are closely related during the micromilling process. However, they have not been sufficiently studied yet. Therefore, the chip shape during the micromilling process is investigated in this research to gain an in-depth understanding of the micromilling process of PEEK. Firstly, a finite-element simulation model is constructed and used to investigate the relationships of feed speed in relation to strain rate and chip shape. Secondly, the chip shape is classified from the experimental results and process intervals are explored corresponding to each kind of chip shape. Then, the relationships between the chip shape and evaluation indexes (milling force F, maximum cutting temperature Tmax, surface roughness Ra) are investigated. It turns out that four main types of chip shapes are produced during the micromilling process of PEEK, namely, the flake chip, the ribbon chip, the curl chip, and the broken chip. Different kinds of chip shapes can be obtained by controlling the process parameters during the micromilling process. The stability of the cutting process can be judged and the machining quality can be initially discerned based on the chip shapes.
ChoudhurySSPandeyMBhattacharyaS. Recent developments in surface modification of PEEK polymer for industrial applications: a critical review. Rev Adhes Adhes2021; 9(401): 10–47750.
2.
VermaSSharmaNKangoS, et al. Developments of PEEK (Polyetheretherketone) as a biomedical material: a focused review. Eur Polym J2021; 147: 110295.
3.
KurtzSMDevineJN. PEEK biomaterials in trauma, orthopedic, and spinal implants. Biomaterials2007; 28(32): 4845–4869.
4.
LiCLiuLShiJY, et al. Clinical and biomechanical researches of polyetheretherketone (PEEK) rods for semi-rigid lumbar fusion: a systematic review. Neurosurg Rev2018; 41(2): 375–389.
5.
ChenLFChenFGateaS, et al. PEEK based cranial reconstruction using thermal assisted incremental sheet forming. Proc IMechE, Part B: J Engineering Manufacture2022; 236(6–7): 997–1004.
6.
CuiZNiJHeL, et al. Investigation of chip formation, cutting force and surface roughness during orthogonal cutting of polytetrafluoroethylene. J Manuf Process2022; 77: 485–494.
7.
XiaoKQZhangLC. The role of viscous deformation in the machining of polymers. Int J Mech Sci2002; 44(11): 2317–2336.
8.
LiYChengXLingS, et al. Study of milling process basics for the biocompatible PEEK material. Mater Res Express2020; 7(1): 015412.
9.
YanYMaoYLiB, et al. Machinability of the thermoplastic polymers: PEEK, PI, and PMMA. Polymers2020; 13(1): 69.
10.
CuiZNiJHeL, et al. Assessment of cutting performance and surface quality on turning pure polytetrafluoroethylene. J Mater Res Technol2022; 20: 2990–2998.
11.
WyethDJ. An investigation into the mechanics of cutting using data from orthogonally cutting Nylon 66. Int J Mach Tools Manuf2008; 48(7–8): 896–904.
12.
GhoshRKnopfJAGibsonDJ, et al. Cryogenic machining of polymeric biomaterials: An intraocular lens case study. In: Medical device materials IV: proceedings of the materials & processes for medical devices conference, Palm Desert, CA, 23–25 September 2007; pp. 54–64.
13.
ChiuWCThoulessMDEndresWJ. An analysis of chipping in brittle materials. Int J Fract1998; 90(4): 287–298.
14.
YanYZhouPWangH, et al. Thermal effect on poly (methyl methacrylate)(PMMA) material removal in the micromilling process. Polymers2020; 12(9): 2122.
15.
JahanMPMaJHansonC, et al. Tool wear and resulting surface finish during micro slot milling of polycarbonates using uncoated and coated carbide tools. Proc IMechE, Part B: J Engineering Manufacture2020; 234(1–2): 52–65.
16.
PetropoulosGMataFDavimJP. Statistical study of surface roughness in turning of peek composites. Mater Des2008; 29(1): 218–223.
17.
TangDWWangCYHuYN, et al. Finite-element simulation of conventional and high-speed peripheral milling of hardened mold steel. Metallurgical Mater Trans A2009; 40(13): 3245–3257.
18.
WangCDingFTangD, et al. Modeling and simulation of the high-speed milling of hardened steel SKD11 (62 HRC) based on SHPB technology. Int J Mach Tools Manuf2016; 108: 13–26.
19.
WangFZhaoJLiA, et al. Effects of cutting conditions on microhardness and microstructure in high-speed milling of H13 tool steel. Int J Adv Manuf Technol2014; 73(1–4): 137–146.
20.
Garcia-GonzalezDRusinekAJankowiakT, et al. Mechanical impact behavior of polyether–ether–ketone (PEEK). Compos Struct2015; 124: 88–99.
21.
GaoXChengXLingS, et al. Research on optimization of micro-milling process for curved thin wall structure. Precis Eng2022; 73: 296–312.
22.
AslantasKAlatrushiLKBedirF, et al. An experimental analysis of minimum chip thickness in micro-milling of two different titanium alloys. Proc IMechE, Part B: J Engineering Manufacture2020; 234(12): 1486–1498.
23.
LaiXLiHLiC, et al. Modelling and analysis of micro scale milling considering size effect, micro cutter edge radius and minimum chip thickness. Int J Mach Tools Manuf2008; 48(1): 1–14.
24.
ChengXLiuJZhengG, et al. Study of microcutting fundamentals for peripheral and end cutting edges in micro-end-milling. J Micromech Microeng2018; 28(1): 015011.
25.
KongJXChenHHeN, et al. Dynamic mechanical property tests and constitutive model of pure iron material. Acta Aeronaut Astronaut Sin2014; 35(7): 2063–2071.
26.
SunXYaoPQuS, et al. Material properties and machining characteristics under high strain rate in ultra-precision and ultra-high-speed machining process: a review. Int J Adv Manuf Technol2022; 120(11–12): 7011–7042.
27.
XieHBYangZQQinN, et al. Strain rate analyses during elliptical vibration cutting of Inconel 718 using finite element analysis, Taguchi method, and ANOVA. Adv Manuf2020; 8(3): 316–330.
28.
WangBLiuZSuG, et al. Investigations of critical cutting speed and ductile-to-brittle transition mechanism for workpiece material in ultra-high speed machining. Int J Mech Sci2015; 104: 44–59.
29.
PhamTHNguyenDTBanhTL, et al. Experimental study on the chip morphology, tool–chip contact length, workpiece vibration, and surface roughness during high-speed face milling of A6061 aluminum alloy. Proc IMechE, Part B: J Engineering Manufacture2020; 234(3): 610–620.
30.
TongXRenYShenJ, et al. Chip formation and the interaction of mesoscopic geometric features of cutter. Proc IMechE, Part B: J Engineering Manufacture2022; 236(3): 270–280.
31.
TrifunovićMMadićMJankovićP, et al. Investigation of cutting and specific cutting energy in turning of POM-C using a PCD tool: analysis and some optimization aspects. J Clean Prod2021; 303: 127043.
32.
KuramE. Micro-milling of unreinforced and reinforced polypropylene. Proc IMechE, Part B: J Engineering Manufacture2019; 233(1): 87–98.
