Study of cutting force and tool wear during turning of aluminium with WC, PCD and HFCVD coated MCD tools
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2020-01-01 |
| Journal | Manufacturing Review |
| Authors | Sisira Kanta Pattnaik, Minaketan Behera, Sachidananda Padhi, Pusparaj Dash, Saroj Kumar Sarangi |
| Institutions | Veer Surendra Sai University of Technology |
| Citations | 7 |
| Analysis | Full AI Review Included |
Technical Documentation and Commercial Analysis: MPCVD Diamond for High-Performance Machining
Section titled âTechnical Documentation and Commercial Analysis: MPCVD Diamond for High-Performance MachiningâSource Paper: S.K. Pattnaik et al., Study of cutting force and tool wear during turning of aluminium with WC, PCD and HFCVD coated MCD tools, Manufacturing Rev. 7, 27 (2020).
Executive Summary
Section titled âExecutive SummaryâThe research provides a compelling validation for utilizing CVD-deposited Micro-Crystalline Diamond (MCD) coatings as a cost-effective, high-performance alternative to traditional HPHT Polycrystalline Diamond (PCD) and Tungsten Carbide (WC) for nonferrous machining.
- Synthesis Validation: Successful deposition of MCD film (HFCVD method, analogous to MPCVD) on WC-Co inserts, utilizing critical chemical pretreatment (Cobalt removal) and 0.50 ”m diamond seeding.
- Performance Parity: MCD coated tools demonstrated cutting force, surface roughness, and tool wear characteristics nearly equivalent to standard HPHT PCD tools.
- Economic Advantage: The study explicitly notes that the CVD MCD solution is five times more cost-effective than HPHT PCD, establishing a strong value proposition for high-volume industrial applications.
- Optimized Tool Life: Minimal tool wear and consistently lower cutting forces were achieved with MCD, particularly at high cutting speeds (325 m/min) and low feed rates (0.09 mm/rev), indicating maximum tool life potential.
- Key Application: The results confirm MPCVD PCD/MCD materials are highly recommended for the dry turning of aluminum and its alloys, optimizing both surface finish and economic efficiency.
Technical Specifications
Section titled âTechnical SpecificationsâHard data points extracted from the experimental methodology and results.
| Parameter | Value | Unit | Context |
|---|---|---|---|
| Substrate Material | WC-6 wt.% Co (K-10) | - | Cutting tool insert (SPGN type) |
| Etching Solution (Co Removal) | HCl+HNO3+H2O (1:1:1 ratio) | - | 15 minutes ultrasonic pretreatment |
| Seeding Particle Size | 0.50 | ”m | Natural Diamond Powder (99.9% purity) |
| Filament Temperature | 2050 ± 50 | °C | HFCVD Tungsten filament |
| Substrate Temperature | 700 ± 20 | °C | Diamond deposition temperature |
| Reaction Pressure | 20 | Torr | HFCVD chamber pressure |
| Gas Composition | 1% CH4 in H2 | - | Carbon source gas mixture |
| Deposition Time | 8 | hr | Required for uniform MCD coating |
| Workpiece Material | Rolled Aluminium | - | Diameter 200 mm, Length 600 mm |
| Cutting Speed (v) Range | 200, 250, 325 | m/min | Machining parameters (Dry) |
| Feed Rate (f) Range | 0.09, 0.12, 0.18 | mm/rev | Machining parameters |
| Depth of Cut (d) | 0.2 | mm | Constant during tests |
| Diamond Raman Shift | 1344 | cm-1 | Peak corresponding to microcrystalline diamond |
Key Methodologies
Section titled âKey MethodologiesâA concise, ordered list detailing the critical steps in the CVD synthesis and characterization processes used in the research.
- Substrate Pretreatment (Cleaning & Etching):
- WC-Co inserts were cleaned in acetone, followed by 15 minutes of ultrasonic chemical etching (HCl+HNO3+H2O) to remove the Cobalt binder layer and induce surface voids for enhanced nucleation.
- Seeding Process:
- Substrates were ultrasonically seeded for 5 minutes in an isopropanol solution containing 0.50 ”m natural diamond powder to ensure high nucleation density within the chemically induced voids.
- HFCVD Deposition:
- Micro-Crystalline Diamond (MCD) film was grown over 8 hours using a tungsten filament carburized at 2050 °C, maintaining the substrate at 700 °C under a 20 Torr pressure with 1% CH4 in H2 gas flow.
- Structural and Phase Characterization:
- SEM: Used to analyze surface morphology after etching, after seeding, and to assess final coating uniformity (Figure 1 & 2) and study flank/rake tool wear (Figure 19).
- XRD: Employed grazing angle X-ray diffraction to confirm the presence of diamond phases (strong 111 and 220 peaks) on the HFCVD coated tool insert.
- Micro Raman Spectroscopy (”-RS): Used to confirm the quality and carbon phase of the MCD film, identifying the characteristic diamond peak at 1344 cm-1.
- Machining Performance Measurement:
- Cutting Force: Dynamic cutting forces were monitored using a Kistler 3D-dynamometer (Model 9257B) during dry turning operations.
- Surface Roughness: Mean roughness (Ra), average peak-to-valley (Rz), and maximum roughness (Rmax) were measured using a Talysurf tester (Subtonic 25).
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & Capabilitiesâ6CCVD provides industry-leading MPCVD technology to replicate, refine, and scale the high-performance diamond tooling results achieved in this study. Our advanced systems offer superior control over grain size (MCD/NCD control), purity, and uniformity compared to the HFCVD method described.
| 6CCVD Solution Category | Application to Research Replication & Extension | 6CCVD Capability & Advantage |
|---|---|---|
| Applicable Materials | Replication of high-performance Micro-Crystalline Diamond (MCD) coatings. | High-Purity MPCVD Polycrystalline Diamond (PCD/MCD): We supply PCD/MCD plates and custom tools with precise grain size control (0.1 ”m to 500 ”m thickness) essential for optimizing wear resistance and achieving targeted surface roughness, validated for nonferrous machining. |
| Substrate & Adhesion Control | Required robust chemical removal of WC-Co binder (Cobalt) and high-density 0.50 ”m diamond seeding. | Expert Pretreatment Engineering: Our in-house PhD team specializes in optimizing substrate preparation, including proprietary chemical etching and enhanced nucleation seeding processes, guaranteeing superior diamond film adhesion and uniformity on carbide inserts. |
| Customization Potential | The study used standard inserts (SPGN120308). Industrial scale-up requires specialized geometries. | Large Format Wafers & Custom Shaping: 6CCVD produces large-area PCD plates up to 125 mm in diameter, allowing customers to laser cut custom insert geometries (e.g., specific nose radii 0.4 mm or 0.8 mm, as cited) optimized for specific aluminum or composite applications. |
| Finishing & Roughness | Required superior surface finish (low Ra values) achieved by the CVD coatings. | Precision Polishing Services: We offer post-deposition polishing to achieve ultra-low surface roughness specifications. SCD can achieve Ra < 1 nm, and Inch-size PCD can achieve Ra < 5 nm, crucial for high-speed finishing operations where surface finish is paramount. |
| Integration Support | Brazing and mounting of diamond inserts (PCD tool was brazed on WC K-10 insert). | Full-Service Metalization: 6CCVD offers internal, high-reliability metalization capabilities (Au, Pt, Pd, Ti, W, Cu) required for robust brazing of diamond tool tips onto tool holders, ensuring structural integrity under high dynamic cutting forces. |
| Engineering Support | Material selection and parameter optimization for cost-effective machining solutions. | Consultation for Machining Projects: 6CCVDâs in-house PhD team provides consultative support for material selection and process optimization tailored to similar nonferrous turning or high-speed composite machining projects, ensuring maximum performance and cost-effectiveness. |
For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.
View Original Abstract
Enormous developmental work has been made in synthesis of metastable diamond by hot filament chemical vapor deposition (HFCVD) method. In this paper, micro-crystalline diamond (MCD) was deposited on WC-6 wt.% Co cutting tool inserts by HFCVD technique. The MCD coated tool was characterized by the scanning electron microscope (SEM), X-ray diffraction (XRD) and micro Raman spectroscopy (Ό-RS). A comparison was made among the MCD tool, uncoated tungsten carbide (WC) tool and polycrystalline diamond (PCD) tool during the dry turning of rolled aluminum. The various major tests were conducted such as surface roughness, cutting force and tool wear, which were taken into consideration to establish a proper comparison among the advanced cutting tools. Surface roughness was measured during machining by Talysurf. The tool wear was studied by SEM after machining. The cutting forces were measured by Kistler 3D-dynamometer during the machining process. The test results indicate that, the CVD coated MCD tool and PCD tool produced almost similar results. But, the price of PCD tools are five times costlier than MCD tools. So, MCD tool would be a better alternative for machining of aluminium.