Additive manufacturing of metal-bonded grinding tools
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2020-03-01 |
| Journal | The International Journal of Advanced Manufacturing Technology |
| Authors | Berend Denkena, Alexander Krödel, Jan Harmes, Fabian Leander Kempf, Tjorben Griemsmann |
| Institutions | Leibniz University Hannover, Laser Zentrum Hannover |
| Citations | 33 |
| Analysis | Full AI Review Included |
Technical Documentation & Analysis: Additive Manufacturing of NiTi-Diamond Grinding Tools
Section titled âTechnical Documentation & Analysis: Additive Manufacturing of NiTi-Diamond Grinding ToolsâThis document analyzes the research concerning the additive manufacturing (AM) of metal-bonded diamond grinding tools using Laser Powder Bed Fusion (LPBF) with Nickel-Titanium (NiTi) matrices. The findings are leveraged to demonstrate how 6CCVDâs advanced MPCVD diamond materials and customization capabilities can accelerate and enhance similar high-performance abrasive projects.
Executive Summary
Section titled âExecutive Summaryâ- Process Validation: The study successfully validates Laser Powder Bed Fusion (LPBF) as a viable technique for manufacturing high-performance NiTi-diamond composite grinding tools.
- Material Performance: Pre-alloyed NiTi powder demonstrated superior performance, resulting in smoother surfaces and a more homogeneous distribution of diamond grains compared to elemental Ni/Ti powder mixtures.
- High Grain Retention: Scratch tests on cemented carbide (tungsten carbide) confirmed that the NiTi bond provides sufficiently high grain retention forces, preventing diamond breakout and ensuring tool resilience.
- Abrasive Capability: The manufactured segments, after a single-step dressing process, achieved an average grain protrusion (Spk) of 8.27 ”m, demonstrating effective abrasive capability for hard materials.
- Process Optimization: LPBF parameters for diamond composites require a lower energy density (El) than those used for manufacturing pure metal components, indicating a necessary adjustment in standard AM recipes.
- Chemical Bonding Potential: The research supports the potential for chemical bonding (e.g., TiC formation) between the diamond and the metallic matrix, which is crucial for maximizing tool lifespan and performance.
Technical Specifications
Section titled âTechnical SpecificationsâThe following hard data points were extracted from the experimental results, focusing on optimal parameters (Parameter Set 4) and performance metrics.
| Parameter | Value | Unit | Context |
|---|---|---|---|
| Matrix Material Composition | NiTi (â 55.5 Ni, 44.5 Ti) | wt% | Pre-alloyed gas atomized powder (#2) |
| Diamond Concentration | 28 | v% | Volume percentage in powder mixture |
| Optimal Laser Power (PL) | 25 | W | Used for scratch test specimens (Set 4) |
| Optimal Scanning Speed (v) | 110 | mm/s | Used for scratch test specimens (Set 4) |
| Energy Density (El) | 0.23 | J/mm | Calculated as PL / v (Set 4) |
| Highest Relative Density (Pure NiTi) | 99.09 | % | Achieved in pure NiTi cubes (PL=50 W, v=110 mm/s, d=50 ”m) |
| Scratch Test Cutting Speed (Vc) | 20 | m/s | Machining cemented carbide |
| Scratch Test Infeed (ae) | 10 | ”m | Depth of cut used in scratch tests |
| Average Grain Protrusion (Spk) | 8.27 | ”m | Measured after dressing/sharpening |
| Specimen Dimensions | 4.95 x 4.95 x 3 | mm | Cuboid test specimens |
Key Methodologies
Section titled âKey MethodologiesâThe experimental procedure focused on optimizing LPBF parameters for the NiTi-diamond composite and validating the abrasive performance.
- Powder Selection and Mixing: Two matrix materials were tested: a conventionally milled elemental mixture (Ni/Ti) and a pre-alloyed gas atomized NiTi powder. Both were mixed with D46 FMD60 diamond grains.
- LPBF System Setup: A laboratory machine equipped with a 50 W fiber laser (1070 nm) and a galvanometric scanner was used. Argon gas maintained an inert atmosphere.
- Parameter Study: A short study was conducted on pure NiTi powder (#2) to determine optimal parameters, varying Laser Power (PL: 20 W to 50 W) and Hatch Distance (d: 20 ”m to 60 ”m) while maintaining a constant scanning speed (110 mm/s).
- Specimen Fabrication: Cuboid test specimens (4.95 mm x 4.95 mm x 3 mm) were built on NiTi sheet substrates using a fixed slice height of 50 ”m. Parameter Set 4 (El = 0.23 J/mm) was selected for final scratch tests due to minimal cracking and tarnish.
- Material Characterization: X-ray Diffraction (XRD) confirmed the presence of cubic and martensitic NiTi phases and the diamond {111} reflection. Scanning Electron Microscopy (SEM) and EDX mapping analyzed diamond dispersion and element homogeneity.
- Abrasive Testing: Segments were bonded to metal pins and dressed using vitrified white corundum (Vc = 10 m/s, ae = 15 ”m). Scratch tests were then performed on polished tungsten carbide (cemented carbide KXF) at Vc = 20 m/s and ae = 10 ”m.
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & CapabilitiesâThis research demonstrates the critical role of high-quality diamond materials and precise interface engineering in advanced manufacturing techniques like LPBF. 6CCVD is uniquely positioned to supply the necessary MPCVD diamond materials and customization services to replicate or extend this research into commercial applications.
| Research Requirement | 6CCVD Solution & Capability | Technical Advantage for Replication/Extension |
|---|---|---|
| Abrasive Material (Industrial Grit) | High-Purity Polycrystalline Diamond (PCD) | We supply high-quality PCD wafers/plates (up to 125mm) for superior thermal stability and consistent microstructure, ideal for high-precision, small-scale tools or thin-film abrasive layers. |
| Chemical Bonding (TiC Interface) | Integrated Metalization Services (Ti, W, Cu) | The paper highlights the need for chemical bonding (TiC). 6CCVD offers in-house metalization (e.g., Ti, W) directly onto the diamond surface, ensuring a robust, pre-engineered carbide interface layer for maximum retention in the NiTi matrix. |
| Custom Geometry (LPBF Segments) | Custom Dimensions & Laser Cutting | We provide SCD (0.1”m - 500”m) and PCD (0.1”m - 500”m) in custom shapes and sizes, ready for integration into AM processes or as substrates (up to 10mm thick) for subsequent LPBF deposition. |
| Thermal Management (High Thermal Conductivity) | Optical Grade Single Crystal Diamond (SCD) | For applications requiring extreme thermal dissipation, our SCD materials offer the highest known thermal conductivity, crucial for minimizing heat damage during high-speed grinding operations. |
| Surface Finish (Post-Processing) | Ultra-Precision Polishing (Ra < 1nm for SCD) | While the paper focuses on abrasive protrusion, 6CCVD can supply tools with ultra-smooth finishes, essential for final lapping or polishing stages of high-value workpieces like cemented carbide. |
Engineering Support
Section titled âEngineering Supportâ6CCVDâs in-house PhD team specializes in the material science of diamond interfaces and thermal management. We offer expert consultation to researchers and engineers developing advanced metal-bonded superabrasives, assisting with material selection, metalization stack design (e.g., Ti/Pt/Au), and optimizing diamond properties (e.g., Boron-Doped Diamond, BDD, for electrochemical grinding applications).
For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.
Tech Support
Section titled âTech SupportâOriginal Source
Section titled âOriginal SourceâReferences
Section titled âReferencesâ- 2017 - 7. WGP-Jahreskongress Aachen, 5.-6. Oktober 2017
- 2017 - Additive Manufacturing Quantifiziert: VisionÀre Anwendungen und Stand der Technik
- 2017 - Additive Manufacturing Quantifiziert: VisionÀre Anwendungen und Stand der Technik [Crossref]