Prediction of micro milling force and surface roughness considering size-dependent vibration of micro-end mill

10.21203/rs.3.rs-937675/v1 ◽

2021 ◽

Author(s):

Du Yicong ◽

Qinghua Song ◽

Liu Zhanqiang

Keyword(s):

Surface Roughness ◽

Size Effect ◽

Surface Topography ◽

Milling Process ◽

Micro Milling ◽

End Mill ◽

Milling Force ◽

Machined Surface ◽

Size Dependent ◽

Micro End Mill

Abstract When the characteristic structure size of the component is at the micron level, the internal crystal grains, grain boundaries and pore defects of the component material with the same size at the micron level cannot be ignored, so the micro-sized component will show different physical properties from the macro-sized component, which is called size effect. Since the tool diameter of micro-end mill is in the micron level, the micro-end mill will also show a significant size effect phenomenon. In addition, in micro milling process, because the surface roughness that affects the performance and service life of micro parts is mainly influenced by the vibration of micro-end mill, in order to enhance the machined surface quality, it is crucial to research the formation mechanism of surface topography in micro milling process. In this paper, a comprehensive method is proposed to predict micro-end mill vibration, micro milling force and surface roughness. At first, a size-dependent dynamic model of micro-end mill is presented based on the strain gradient elasticity theory (SGET). Secondly, considering the feedback of micro-end mill vibration, the micro milling force model is presented and solved through iterative method. Then the machined surface topography is simulated through the actual cutting edge trajectory considering the micro-end mill size-dependent vibration and material elastic recovery. The results show that the vibration of the micro-end mill will increase the micro milling force and surface roughness. In order to verify the accuracy and efficiency of the presented method, experiments are performed, and it is found that the experimental results are consistent with the predicted results.

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Cutting Performance of Different Coated Micro End Mills in Machining of Ti-6Al-4V

Micromachines ◽

10.3390/mi9110568 ◽

2018 ◽

Vol 9 (11) ◽

pp. 568 ◽

Cited By ~ 5

Author(s):

Zhiqiang Liang ◽

Peng Gao ◽

Xibin Wang ◽

Shidi Li ◽

Tianfeng Zhou ◽

...

Keyword(s):

Tool Wear ◽

Cutting Edge ◽

Micro Milling ◽

End Mill ◽

Coating Materials ◽

Edge Chipping ◽

Workpiece Surface ◽

Micro End Mill ◽

End Mills ◽

Flank Surface

Tool wear is a significant issue for the application of micro end mills. This can be significantly improved by coating materials on tool surfaces. This paper investigates the effects of different coating materials on tool wear in the micro milling of Ti-6Al-4V. A series of cutting experiments were conducted. The tool wear and workpiece surface morphology were investigated by analyzing the wear of the end flank surface and the total cutting edge. It was found that, without coating, serious tool wear and breakage occurred easily during milling. However, AlTiN-based and AlCrN-based coatings could highly reduce cutting edge chipping and flank wear. Specifically, The AlCrN-based coated mill presented less fracture resistance. For TiN coated micro end mill, only slight cutting edge chipping occurred. Compared with other types of tools, the AlTiN-based coated micro end mill could maximize tool life, bringing about an integrated cutting edges with the smallest surface roughness. In short, the AlTiN-based coating material is recommended for the micro end mill in the machining of Ti-6Al-4V.

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Experimental Study on Machinability of Zr-Based Bulk Metallic Glass during Micro Milling

Micromachines ◽

10.3390/mi11010086 ◽

2020 ◽

Vol 11 (1) ◽

pp. 86 ◽

Cited By ~ 1

Author(s):

Tao Wang ◽

Xiaoyu Wu ◽

Guoqing Zhang ◽

Bin Xu ◽

Yinghua Chen ◽

...

Keyword(s):

Surface Roughness ◽

Metallic Glass ◽

Bulk Metallic Glass ◽

Feed Rate ◽

Rotation Speed ◽

Amorphous Structure ◽

Micro Milling ◽

Depth Of Cut ◽

Milling Force ◽

Coated Cemented Carbide

The micro machinability of Zr41.2Ti13.8Cu12.5Ni10Be22.5 bulk metallic glass (BMG) was investigated by micro milling with coated cemented carbide tools. The corresponding micro milling tests on Al6061 were conducted for comparison. The results showed that the tool was still in stable wear stage after milling 300 mm, and the surface roughness Ra could be maintained around 0.06 μm. The tool experienced only slight chipping and rubbing wear after milling the BMG, while a built-up edge and the coating peeling off occurred severely when milling Al6061. The influence of rotation speed on surface roughness was insignificant, while surface roughness decreased with the reduction of feed rate, and then increased dramatically when the feed rate was below 2 μm/tooth. The surface roughness increased gradually with the axial depth of cut (DOC). Milling force decreased slightly with the increase in rotation speed, while it increased with the increase in axial DOC, and the size effect on milling force occurred when the feed rate decreased below 1 μm/tooth. The results of X-ray diffraction (XRD) showed that all milled surfaces were still dominated by an amorphous structure. This study could pave a solid foundation for structural and functional applications.

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Machinability Research on the Micro-Milling for Graphene Nano-Flakes Reinforced Aluminum Alloy

Metals ◽

10.3390/met9101102 ◽

2019 ◽

Vol 9 (10) ◽

pp. 1102 ◽

Cited By ~ 2

Author(s):

Na ◽

Xu ◽

Han ◽

Liu ◽

Lu

Keyword(s):

Surface Roughness ◽

Aluminum Alloy ◽

Chip Morphology ◽

Matrix Alloy ◽

Micro Milling ◽

Milling Force ◽

Machined Surface ◽

Graphene Nanoflakes ◽

Aluminum Chip ◽

Powder Metallurgy Approach

In this paper, plain aluminum was chosen as matrix alloy and graphene reinforced aluminum alloy composites was successfully prepared via powder metallurgy approach. Micro-milling experiments were conducted to explore the effect of varying graphene nanoflakes (GNFs) content (0.5%, 1.0%, and 1.5% by weight) on the machinability of composites and their machining results were compared with that of plain aluminum. Chip morphology, milling force, and machined surface morphology were used as the machinability measures. Experiment results showed that when the content of GNFs is less than 1.5%, the grain refinement of GNFs plays a major role. The hardness and density of the composites are increased. When the content of GNFs is more than 1.5%, the agglomeration phenomenon is obvious, which reduces the hardness and density of the composites. Micro-milling results show that the milling force is the highest when the GNFs content is 1%, and curling degree of chips increased as FPT increase for a certain content of graphene of composites. Furthermore, when the content of GNFs in composites is more than 1%, the surface roughness of milling grooves is greatly improved, which may be related to the lubrication of graphene and the formation of continuous chips.

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Influence of Pulsed Magnetic Treatment on Wear of Carbide Micro-end-Mill

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1136.143 ◽

2016 ◽

Vol 1136 ◽

pp. 143-148 ◽

Cited By ~ 2

Author(s):

Zhi Qiang Liang ◽

Li Ping Ma ◽

Xi Bin Wang ◽

Wen Xiang Zhao ◽

Tian Feng Zhou ◽

...

Keyword(s):

Aluminum Alloy ◽

Magnetic Treatment ◽

Micro Milling ◽

End Mill ◽

Friction Behavior ◽

Workpiece Material ◽

Wear Area ◽

Paramagnetic Material ◽

Micro End Mill ◽

Edge Wear

This study is carried out to investigate the influence of pulsed magnetic treatment on wear of carbide micro-end-mill. To analyze the friction behavior of micro-end-mill with workpiece, the special micro-end-mill with a chisel is fabricated and used in micro-milling experiments. A paramagnetic material aluminum alloy is employed as workpiece material. The experimental results indicated 17% and 27 % reductions in maximum minor flank wear width and chisel edge wear area of micro-end-mill after pulsed magnetic treatment, respectively. However, the surface roughness and morphology of machined aluminum alloy have no obvious changes with or without pulsed magnetic treatment. Consequently, the reduction of tool wear during milling aluminum alloy can be mainly attributed to the improvement of mechanical properties of carbide tool materials after pulsed magnetic treatment.

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Investigation of the Effect of End Mill-Geometry on Roughness and Surface Strain-Hardening of Aluminum Alloy AA6082

Materials ◽

10.3390/ma13143078 ◽

2020 ◽

Vol 13 (14) ◽

pp. 3078

Author(s):

Pavel Filippov ◽

Michael Kaufeld ◽

Martin Ebner ◽

Ursula Koch

Keyword(s):

Surface Roughness ◽

Strain Hardening ◽

Cutting Edge ◽

Surface Strain ◽

Micro Milling ◽

End Mill ◽

Cutting Edge Radius ◽

Hardened Zone ◽

Edge Radius ◽

Machined Surfaces

Micro-milling is a promising technology for micro-manufacturing of high-tech components. A deep understanding of the micro-milling process is necessary since a simple downscaling from conventional milling is impossible. In this study, the effect of the mill geometry and feed per tooth on roughness and indentation hardness of micro-machined AA6082 surfaces is analyzed. A solid carbide (SC) single-tooth end-mill (cutting edge radius 670 nm) is compared to a monocrystalline diamond (MD) end-mill (cutting edge radius 17 nm). Feed per tooth was varied by 3 μm, 8 μm and 14 μm. The machined surface roughness was analyzed microscopically, while surface strain-hardening was determined using an indentation procedure with multiple partial unload cycles. No significant feed per tooth influence on surface roughness or mechanical properties was observed within the chosen range. Tools’ cutting edge roughness is demonstrated to be the main factor influencing the surface roughness. The SC-tool machined surfaces had an average Rq = 119 nm, while the MD-tool machined surfaces reached Rq = 26 nm. Surface strain-hardening is influenced mainly by the cutting edge radius (size-effect). For surfaces produced with the SC-tool, depth of the strain-hardened zone is higher than 200 nm and the hardness increases up to 160% compared to bulk. MD-tool produced a thinner strain-hardened zone of max. 60 nm while the hardness increased up to 125% at the surface. These findings are especially important for the high-precision manufacturing of measurement technology modules for the terahertz range.

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Micro milling characteristics of LS-WEDM fabricated helical and corrugated micro end mill

International Journal of Mechanical Sciences ◽

10.1016/j.ijmecsci.2019.105277 ◽

2020 ◽

Vol 167 ◽

pp. 105277 ◽

Cited By ~ 5

Author(s):

Y. Sun ◽

Y.D. Gong ◽

X.L. Wen ◽

G.Q. Yin ◽

F.T. Meng

Keyword(s):

Micro Milling ◽

End Mill ◽

Micro End Mill ◽

Milling Characteristics

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Research on Tool Wear of PCD Micro End Mill in Machining of ZrO2 Ceramics

Materials Science Forum ◽

10.4028/www.scientific.net/msf.800-801.20 ◽

2014 ◽

Vol 800-801 ◽

pp. 20-25 ◽

Cited By ~ 2

Author(s):

Shu Long Wang ◽

Liang Li ◽

Ning He ◽

Rong Bian ◽

Zhong Bo Zhan ◽

...

Keyword(s):

Tool Wear ◽

Cutting Force ◽

Cutting Tool ◽

Micro Milling ◽

Bottom Surface ◽

Machining Accuracy ◽

End Mill ◽

Micro End Mill ◽

Wear Tool ◽

Tool Diameter

This paper presents a study on the tool wear of micro PCD end mill when machining ZrO2 ceramics. The cutting tool used was a self-designed PCD micro end mill with 1 mm in diameter and single flute. Experiments were conducted on a self-developed micro-milling machine tool. The tool wear characters and progress during the groove milling has been observed. The cutting force and machining accuracy of the grooves also have been studied. Based on the results, it is found that tool wear is mainly on the bottom surface; the cutting force increases with the progress of tool wear; tool wear also affect the width of machined grooves due to the decrease of effective tool diameter.

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