Fabrication of PCD Skiving Cutter by UV Nanosecond Laser

At a Glance

Metadata	Details
Publication Date	2021-07-19
Journal	Materials
Authors	Jianlei Cui, Xuyang Fang, Xiangyang Dong, Xuesong Mei, Kai‐Da Xu
Institutions	Xi’an Jiaotong University
Citations	12
Analysis	Full AI Review Included

Executive Summary

This documentation analyzes the fabrication of high-precision Polycrystalline Diamond (PCD) skiving cutters using a two-step UV Nanosecond Laser (NSL) process, highlighting 6CCVD’s capability to supply the necessary advanced diamond materials.

Application Focus: High-precision fabrication of PCD skiving cutters for miniature parts in aerospace and ultra-precision machinery.
Methodology: A two-step laser machining process combining orthogonal irradiation (roughing) and tangential irradiation (finishing/polishing) using a 355 nm UV nanosecond laser.
Performance Achieved: A superior cutting edge was obtained with a final contour accuracy (Rt) of 5.6 µm.
Material Integrity: Raman spectroscopy confirmed that the two-step UV NSL process successfully avoided phase transition damage, maintaining the strong sp3 diamond structure (no graphite formation).
Mechanism Validation: Finite Element Analysis demonstrated that the UV wavelength (355 nm) enables a photochemical ablation mechanism, resulting in a cleaner, flatter morphology and significantly less graphitization depth compared to visible (532 nm) or infrared (1064 nm) lasers.
Optimal Parameters: Key processing parameters for minimizing Rt were identified as a 3 µm line interval, +100 µm positive defocus, and 400 mm/s scanning speed.

Technical Specifications

The following hard data points were extracted from the experimental results and simulation analysis:

Parameter	Value	Unit	Context
Final Contour Accuracy (R<sub>t</sub>)	5.6	µm	Achieved after two-step finishing
PCD Blank Diameter	20	mm	Material sample size
PCD Blank Thickness	2	mm	Material sample size
Laser Wavelength (Experimental)	355	nm	UV Nanosecond Laser (NSL)
Laser Pulse Width (Experimental)	10	ns	NSL
Optimal Line Interval	3	µm	Parameter for minimum R<sub>t</sub>
Optimal Scanning Speed	400	mm/s	Parameter for minimum R<sub>t</sub>
Optimal Defocus Amount	+100	µm	Positive defocus for minimum R<sub>t</sub>
Diamond Graphitization Threshold	1233	K	Temperature for sp<sup>3</sup> to sp<sup>2</sup> transition
Graphite Gasification Threshold	4827	K	Temperature for removal
UV Absorptivity (355 nm)	Approx. 0.95	N/A	Highest absorption rate compared to IR/Green

Key Methodologies

The fabrication relied on a specialized two-step laser machining process optimized for PCD material removal and surface quality control.

Material Preparation: A PCD diamond blank (20 mm diameter, 2 mm thickness) was used as the starting material.
Equipment Setup: An INNO-FOTIA-355-OEM-2 UV Nanosecond Laser (355 nm, 10 ns) was integrated with a 4-axis CNC motion platform (XYZ linear and C rotary axis).
Roughing Machining (Orthogonal Exposure):
- Irradiation: Laser beam transmission direction was vertical (perpendicular) to the horizontal processed surface.
- Goal: Rapid, bulk material removal to establish the basic contour shape of the skiving cutter.
Finishing Machining (Tangential Exposure):
- Irradiation: Laser beam was parallel to the processed surface, scanning along the cutting edge contour.
- Goal: Polish the main flank face, repair the cutting edge shape, and minimize Rt by limiting absorbed energy density.
Parameter Optimization: Processing parameters (line interval, scanning speed, defocusing amount) were systematically adjusted to regulate energy density and minimize Rt defects.
Surface Characterization: Raman spectroscopy was used to confirm the absence of the D-band (1350 cm-1) and G-band (1590 cm-1) peaks on the finished flank face, verifying the successful suppression of sp2 (graphite) phase transition.

6CCVD Solutions & Capabilities

This research validates the use of high-quality PCD and precise laser processing for demanding tooling applications. 6CCVD is uniquely positioned to supply the foundational materials and engineering support required to replicate and advance this technology.

Research Requirement (Paper)	6CCVD Solution & Capability	Technical Advantage
Material: High-Quality Polycrystalline Diamond (PCD)	Optical Grade PCD Wafers	Our MPCVD PCD offers superior uniformity and purity, essential for predictable, low-damage UV laser ablation and high tool life.
Dimensions: 20 mm diameter, 2 mm thickness	Custom Dimensions up to 125 mm	We supply PCD plates/wafers up to 125 mm diameter and thicknesses up to 500 µm, allowing for scaling of this tooling application.
Surface Finish: Need for smooth starting surface (low R<sub>t</sub>)	Ultra-Precision Polishing Services	We offer PCD polishing down to Ra < 5 nm (for inch-size wafers), providing an ideal, defect-free surface that minimizes subsequent laser finishing time.
Tool Integration: Need for complex geometry and mounting	Custom Laser Cutting & Metalization	We provide in-house laser cutting for complex shapes and offer custom metalization (e.g., Ti/Pt/Au, W, Cu) for robust tool mounting and thermal management.
Process Optimization: Need to minimize graphitization	Engineering Support & Material Consultation	6CCVD’s in-house PhD team specializes in diamond material interaction and can assist engineers in selecting the optimal PCD grade to maximize UV absorption efficiency and minimize thermal damage for similar PCD Skiving Cutter projects.

For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.

View Original Abstract

Polycrystalline diamond (PCD) skiving cutter has dominated research in recent years. However, the traditional methods of fabrication have failed to cut the diamond with high quality. We propose the two-step laser machining process combining roughing machining with orthogonal irradiation and finishing machining with tangential irradiation. In addition, the processing effect and mechanism of different lasers on the diamond were investigated by a finite element analysis. It’s proved that the ultraviolet nanosecond laser is an excellent machining method for the processing of diamond. Furthermore, the effect of the processing parameters on the contour accuracy (Rt) was studied. The result indicates that the Rt value decreases first and then increases as the increase of the line interval, scanning speed and defocusing amount (no matter positive or negative defocus). Further, Raman spectroscopy was applied to characterize the diamond surface under different cutting methods and the flank face of the tool after processing. Finally, a high-quality PCD skiving cutter was obtained with an Rt of 5.6 µm and no phase transition damage.

Tech Support

Original Source

DOI: https://doi.org/10.3390/ma14144027

References

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