Optimization of Micro Milling Process

The discrete element method (DEM) is applied to glass micromachining in this study. By three standard tests the discrete element model is established to match the main mechanical properties of glass. Then, indentating, cutting, micro milling process are simulated. Results show that the vertical damage depth is prevented from reaching the final machined surface in cutting process. Tool rake angle is the most remarkable factor influencing on the chip deformation and cutting force. The final machined surface is determined by the minimum cutting thickness per edge. Different cutting thickness, cutter shape and spindle speed largely effect on the mechanism of glass.

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Experimental investigation of the influence of cutting parameters on surface quality and on the special characteristics of micro-milled surfaces of hardened steels

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/09544062211013064 ◽

2021 ◽

pp. 095440622110130

Author(s):

Barnabás Zoltán Balázs ◽

Márton Takács

Keyword(s):

Surface Quality ◽

Surface Profile ◽

Cutting Parameters ◽

Relevant Information ◽

Milling Process ◽

Micro Milling ◽

Machined Surface ◽

Analysis Of Dynamics ◽

Five Axis ◽

Coated Carbide

Micro-milling is one of the most essential technologies to produce micro components, but due to the size effect, it has many special characteristics and challenges. The process can be characterised by strong vibrations, relatively large run-out and tool deformation, which directly affects the quality of the machined surface. This paper deals with a detailed investigation of the influence of cutting parameters on surface roughness and on the special characteristics of micro-milled surfaces. Several systematic series of experiments were carried out and analysed in detail. A five-axis micromachining centre and a two fluted, coated carbide micro-milling tool with a diameter of 500 µm were used for the tests. The experiments were conducted on AISI H13 hot-work tool steel and Böhler M303 martensitic corrosion resistance steel with a hardness of 50 HRC in order to gain relevant information of machining characteristics of potential materials of micro-injection moulding tools. The effect of the cutting parameters on the surface quality and on the ratio of Rz/ Ra was investigated in a comprehensive cutting parameter range. ANOVA was used for the statistical evaluation. A novel method is presented, which allows a detailed analysis of the surface profile and repetitions, and identify the frequencies that create the characteristic profile of the surface. The procedure establishes a connection between the frequencies obtained during the analysis of dynamics (forces, vibrations) of the micro-milling process and the characterising repetitions and frequencies of the surface.

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Schneidkantenpräparation von VHM-Mikrofräsern*/Cutting edge preparation of cemented carbide micro milling tools – A comparison of different fine machining processes

wt Werkstattstechnik online ◽

10.37544/1436-4980-2015-11-12-45 ◽

2015 ◽

Vol 105 (11-12) ◽

pp. 805-811

Author(s):

E. Uhlmann ◽

D. Oberschmidt ◽

A. Löwenstein ◽

M. Polte ◽

I. Winker

Keyword(s):

Tool Wear ◽

Milling Process ◽

Cutting Edge ◽

Micro Milling ◽

Machining Processes ◽

Process Reliability ◽

Cutting Edge Preparation ◽

Milling Tools ◽

Edge Preparation

Die Prozesssicherheit beim Mikrofräsen lässt sich mit einer gezielten Schneidkantenverrundung erheblich steigern. Dabei werden durch verschiedene Präparationstechnologien unterschiedliche Geometrien und Einflüsse auf den Fräsprozess erzeugt. Der Fachbeitrag behandelt den Einsatz präparierter Mikrowerkzeuge in Zerspanversuchen, in denen auf die Zerspankräfte, den Verschleiß sowie die Oberflächengüten eingegangen wird.   Process reliability in micro milling can be increased by a defined cutting edge preparation. Different cutting edge preparations cause different effects on tool behavior in the downstream micro milling process. In this paper, the process forces, the tool wear and the surface quality of prepared micro milling tools are characterized in cutting tests.

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Measurement of Micro Burr and Slot Widths through Image Processing: Comparison of Manual and Automated Measurements

10.21203/rs.3.rs-308109/v1 ◽

2021 ◽

Author(s):

FATIH AKKOYUN ◽

Ali Ercetin ◽

Kubilay Aslantas

Keyword(s):

Image Processing ◽

Cutting Tools ◽

Cutting Parameters ◽

Helix Angle ◽

Milling Process ◽

Micro Milling ◽

Inconel 718 Alloy ◽

Sem Images ◽

Automated Measurements ◽

Cutting Length

Abstract In this study, the burr and slot widths formed after micro-milling process are investigated using a rapid and accurate image processing method. The measurements are obtained by processing the images and results were compared with a manual measurement method. In the cutting experiment stage, Inconel 718 alloy was chosen as the workpiece and cutting tools with various specific properties were used. The images of the burr and slots were captured using scanning electron microscope (SEM). Different tool geometries and cutting parameters were considered for choosing the SEM images. Captured images were processed with a computer vision software which was written in C + + programming language and open-sourced computer library (Open CV). The demonstrated approach was successfully measured the slot and burr widths in plain and complex conditions where slot and burr are nested. According to the close findings of manual and automated measurements, it was observed that burr widths increased especially at the down milling sides and slot widths decreased due to the increased cutting length. Specific tool properties such as number of cutting edge, helix angle and cutting length affected the slot and burr widths. It was determined that there is a good correlation between automated and manual measurements of slot and burr widths. The accuracy of the proposed method is above 91%, 98%, and 99% for up milling, down milling, and slot measurements, respectively.

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A Study on Micro-Milling Process of Multi-Directional Carbon Fiber Reinforced Plastic Composite Using Nano-Solid Dry Lubrication

Volume 2: Manufacturing Processes; Manufacturing Systems; Nano/Micro/Meso Manufacturing; Quality and Reliability ◽

10.1115/msec2020-8458 ◽

2020 ◽

Author(s):

Jin Woo Kim ◽

Jungsoo Nam ◽

Jaehun Jeon ◽

Sang Won Lee

Keyword(s):

Carbon Nanotubes ◽

Carbon Fiber ◽

Multiwall Carbon Nanotubes ◽

Milling Process ◽

Graphene Nanoplatelets ◽

Micro Milling ◽

Carbon Fiber Reinforced Plastic ◽

Fiber Reinforced Plastic ◽

Reinforced Plastic ◽

Multiwall Carbon

Abstract In this research, the micro-milling process using nano-solid dry lubrication is studied for machining multidirectional carbon fiber reinforced plastic (MD-CFRP). For the nano-solid dry lubrication, two kinds of graphene nanoplatelets and multiwall carbon nanotubes are used as nanoparticles. The workpiece is an MD-CFRP composite in which 10 plies of prepreg are laminated and it consists of four carbon fiber orientations — 0°, 45°, 90°, 135°. After a series of micro-milling experiments, the workpiece surface quality and tool wear are investigated. Overall, it is found that the nano-solid dry lubrication can improve the surface quality and reduce the tool wear. In particular, larger graphene nanoplatelets (xGnP H-5) are more advantageous than smaller graphene nanoplatelets (xGnP C-750). In addition, multiwall carbon nanotubes having a tube-shape structure are less effective than graphene nanoplatelets having a two-dimensional thin sheet shape for enhancing the micro-milling performances, which may be due to better lubrication effect with the graphene nanoplatelets’ sliding phenomenon at the cutting region.

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An accurate instantaneous uncut chip thickness model combining runout effect in micro-milling using cutters with the non-uniform helix and pitch angles

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1177/0954405419889198 ◽

2019 ◽

Vol 234 (5) ◽

pp. 859-870 ◽

Cited By ~ 4

Author(s):

Qiang Guo ◽

Yan Jiang ◽

Zhibo Yang ◽

Fei Yan

Keyword(s):

Tool Path ◽

Chip Thickness ◽

Milling Process ◽

Machining Process ◽

Micro Milling ◽

Cutter Runout ◽

Model Combining ◽

Key Factor ◽

Cutting Point ◽

Instantaneous Uncut Chip Thickness

As a key factor, the accuracy of the instantaneous undeformed thickness model determines the force-predicting precision and further affects workpiece machining precision in the micro-milling process. The runout with five parameters affects the machining process more significantly compared with macro-milling. Furthermore, modern industry uses cutters with non-uniform pitch and helix angles more and more common for their excellent properties. In this article, an instantaneous undeformed thickness model is presented regarding cutter runout, variable pitch, and helix angles in the micro-milling process. The cutter edge with the cutter runout effect is modeled. Then, the intersecting ellipse between the plane vertical to the spindle axis and the cutter surface which is a cylinder can be gained. Based on this, the points, which are used to remove the material, on the ellipse as well as cutter edges are calculated. The true trochoid trajectory for each cutting point along the tool path is built. Finally, the instantaneous undeformed thickness values are computed using a numerical algorithm. In addition, this article analyzes runout parameters’ effects on the instantaneous undeformed thickness values. After that, helix and pitch angles’ effects on the instantaneous undeformed thickness are studied. Ultimately, the last section verifies the correctness and validity of the instantaneous undeformed thickness model based on the experiment conducted in the literature.

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