Modeling and Cutting Mechanics in the Milling of Polymer Matrix Composites
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2025-06-25 |
| Journal | Materials |
| Authors | Krzysztof CiecielÄ g, Andrzej Kawalec, MichaĹ Gdula, Piotr Ĺťurek |
| Institutions | Lublin University of Technology, RzeszĂłw University of Technology |
| Analysis | Full AI Review Included |
Executive Summary
Section titled âExecutive SummaryâThis study successfully modeled and analyzed the cutting mechanics during the milling of Glass Fiber Reinforced Polymers (GFRP) and Carbon Fiber Reinforced Polymers (CFRP) using Response Surface Methodology (RSM).
- Modeling Accuracy: Mathematical models derived using RSM/ANOVA accurately predicted cutting forces (Fx and Fy). Polycrystalline Diamond (PCD) tools yielded the highest coefficient of determination (R2) for force models (0.90-0.99) across both materials.
- Key Process Parameter: Feed per tooth (fz) was confirmed as the most significant technological parameter influencing both the feed force (Fx) and the main (tangential) cutting force (Fy).
- Cost-Effective Tooling Strategy: Similar maximum main cutting forces (Fy, 140 N to 180 N) were achieved using inexpensive uncoated carbide tools (high rake angle, 29.2°) compared to expensive PCD tools (low rake angle, 8°). This supports using cheaper tools for low-cost, sustainable production if only the main force component is considered.
- Material Resistance: CFRP exhibited higher cutting resistance (kc) than GFRP in most tests, confirming its greater difficulty in machining. The overall cutting resistance ranged from 3.8 N/mm2 to 15.5 N/mm2.
- Feed Force Difference: The maximum feed force (Fx) recorded during CFRP milling was approximately twice as high as that recorded for GFRP under identical PCD tool conditions (max Fx up to 133 N for CFRP vs. 58 N for GFRP).
Technical Specifications
Section titled âTechnical Specificationsâ| Parameter | Value | Unit | Context |
|---|---|---|---|
| Composite Type 1 | EGL/EP 3200-120 | N/A | Glass Fiber Reinforced Polymer (GFRP) |
| Composite Type 2 | HexPly AG193PW/3501/6SRC41 | N/A | Carbon Fiber Reinforced Polymer (CFRP) |
| Lay-up Configuration | 0°/90° | N/A | 40 layers, 0.25 mm prepreg thickness |
| Cutting Speed (vc) Range | 54.5 to 365.5 | m/min | RSM experimental range |
| Feed per Tooth (fz) Range | 0.05 to 0.54 | mm/tooth | RSM experimental range |
| Depth of Cut (ap) | 1.0 | mm | Constant for all tests |
| Uncoated Carbide Rake Angle | 29.2 | ° | XOEX060204FR-E03 (H15) |
| Coated Carbide Rake Angle | 20.2 | ° | XOMX060204R-M05 (F40M) |
| PCD Rake Angle | 8.0 | ° | XOEX060204FR (PCD 05) |
| Maximum Main Force (Fy) Range | 140 to 180 | N | Across all tools and materials |
| Maximum Feed Force (Fx) Range | 46 to 133 | N | Across all tools and materials |
| Cutting Resistance (kc) Range | 3.8 to 15.5 | N/mm2 | Determined for highest force values |
| Highest Coefficient of Determination (R2) | 0.99 | N/A | Fy model using PCD tool on GFRP |
Key Methodologies
Section titled âKey MethodologiesâThe study utilized a systematic experimental approach based on Response Surface Methodology (RSM) combined with Analysis of Variance (ANOVA) to model cutting forces.
- Sample Preparation: GFRP and CFRP samples (10 x 50 x 150 mm plates) were prepared using the autoclave technique, cured for 2 hours at 177 °C (¹2 °C) under 0.3 MPa pressure, and conditioned in a controlled environment (18 °C to 30 °C, humidity below 60%).
- Experimental Design: A two-factor Central Composite Rotatable Design (CCRD) was implemented using Statistica 13.3 software. The independent variables were Cutting Speed (vc) and Feed per Tooth (fz).
- Milling Setup: Experiments were conducted on a DMG DMU 100 monoBLOCK milling center using a 12 mm nominal diameter indexable cutter body. Full symmetric milling (width of cut ae = cutter diameter) was performed.
- Tooling: Three types of SECO inserts were tested, differing in material and rake angle (Îł):
- Uncoated Carbide (H15, γ = 29.2°).
- TiAlN-Coated Carbide (F40M, γ = 20.2°).
- Polycrystalline Diamond (PCD 05, γ = 8°).
- Force Measurement: Cutting forces (Fx, Fy) were measured using a Kistler 9123C piezoelectric rotating four-component dynamometer mounted directly in the spindle.
- Data Acquisition and Filtering: Data was recorded using a KUSB-3100 board and quickDAQ software at a sampling frequency of 10 kHz. Raw signals were filtered using a proprietary Chebyshev low-pass filter implemented in MATLAB (vR2022b).
- Modeling and Analysis: ANOVA was used to select appropriate quadratic models (Y = β0 + β1X1 + β2X2 + β11(X1)2 + β22(X2)2 + β12X1X2) for Fx and Fy, and the Coefficient of Determination (R2) was calculated to assess model fit.
- Cutting Resistance Calculation: Cutting resistance (kc) was calculated using the formula kc = Fx,y / (ap x ae), where ap is the depth of cut and ae is the width of cut (12 mm).
Commercial Applications
Section titled âCommercial ApplicationsâThe findings provide critical data for optimizing machining processes and reducing manufacturing costs for high-performance composite materials used in demanding engineering applications.
| Industry/Sector | Relevance to Machining Composites |
|---|---|
| Aerospace and Defense | Requires precise milling of CFRP and GFRP components (e.g., airframe structures, satellite parts). The force models enable predictive control to minimize defects like delamination. |
| High-Performance Automotive | Uses composites for lightweight chassis and body panels. The study provides data for selecting optimal feed rates (fz) to balance throughput and surface quality. |
| Tooling and Manufacturing Engineering | Offers a validated strategy for tool selection based on cost and performance. The ability to substitute expensive PCD tools with high-rake-angle uncoated carbide tools for similar Fy results provides significant cost savings (carbide inserts are approximately 8 times less expensive than PCD inserts). |
| Medical Devices | Composites are used in specialized equipment requiring high corrosion resistance and precise geometry. Accurate force modeling ensures dimensional stability during machining. |
| Process Optimization | The identification of feed per tooth (fz) as the dominant factor allows engineers to focus optimization efforts on this parameter to control cutting forces and minimize mechanical load on the workpiece and tool. |
View Original Abstract
The study investigates the problem of modeling cutting-force components through response surface methodology and reports the results of an investigation into the impact of machining parameters on the cutting mechanics of polymer-matrix composites. The novelty of this study is the modeling of cutting forces and the determination of mathematical models of these forces. The models describe the values of forces as a function of the milling parameters. In addition, the cutting resistance of the composites was determined. The influence of the material and rake angle of individual tools on the cutting force components was also determined. Measurements of the main (tangential) cutting force showed that, using large rake angles for uncoated carbide tools, one could obtain maximum force values that were similar to those obtained with polycrystalline diamond tools with a small rake angle. The results of the analysis of the tangential component of cutting resistance showed that, regardless of the rake angle, the values range from 140 N to 180 N. An analysis of the feed component of cutting resistance showed that the maximum values of this force ranged from 46 N to 133 N. The results showed that the highest values of the feed component of cutting resistance occurred during the machining of polymer composites with carbon fibers and that they were most affected by feed per tooth. It was also shown that the force models determined during milling with diamond insert tools had the highest coefficient of determination in the range of 0.90-0.99. The cutting resistance analysis showed that the values tested are in the range of 3.8 N/mm2 to 15.5 N/mm2.
Tech Support
Section titled âTech SupportâOriginal Source
Section titled âOriginal SourceâReferences
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