Investigating the Influence of Laser-Etched Straight and Wavy Textures on Grinding Efficiency and Tool Quality of WC–Co Carbide Cutting Tools

At a Glance

Metadata	Details
Publication Date	2025-01-24
Journal	Materials
Authors	Chao Li, Tielin Li, Xiaohong Zhang, Tianzhongsen He, Lijuan Su
Institutions	Hunan Institute of Science and Technology
Citations	3
Analysis	Full AI Review Included

Executive Summary

This study successfully demonstrated the optimization of WC-Co cemented carbide cutting tool quality and grinding efficiency through pre-grinding laser surface texturing (LST), focusing on straight and wavy patterns.

Grinding Force Reduction: The wavy texture pattern provided the most significant performance gain, achieving a maximum reduction of 53.7% in normal grinding force and 51.2% in tangential grinding force compared to untextured tools.
Surface Quality Improvement: LST significantly improved surface integrity. Wavy-textured tools showed the best results, reducing surface roughness (S_a) by up to 38.9% compared to conventionally ground (untextured) tools.
Enhanced Edge Integrity: Laser texturing dramatically mitigated edge chipping. The maximum reduction in edge chipping length for wavy-textured tools was 66.6%. Textured tools maintained acceptable edge quality up to a grinding depth (a_p) of 20 µm, whereas untextured tools failed specifications at 10 µm.
Mechanism Validation: The textured grooves act as microfluidic channels, promoting coolant penetration, enhancing chip evacuation, and reducing friction and thermal stress concentration during grinding.
CFRP Machining Performance: Tools processed with laser-assisted grinding produced superior surface quality on turned CFRP bars, exhibiting less fiber pull-out and fewer fiber voids due to the improved stability and quality of the cutting edge.
Processing Method: Textures were created using an ultrafast picosecond pulsed laser, ensuring sharp boundaries and minimal thermal damage (recast layer) to the WC-Co substrate.

Technical Specifications

Parameter	Value	Unit	Context
Tool Material Composition	94 / 6	wt%	WC / Co
Tool Hardness	1700	HV	WC-Co Carbide
WC Grain Size	0.7	µm	WC-Co Carbide
Laser Type	Picosecond Pulsed	N/A	Ablation System (BC-2900)
Average Laser Power (P_avg)	9.5	W	Laser Texturing
Pulse Frequency (f_p)	60	kHz	Laser Texturing
Scanning Spacing (d_ss)	5	µm	Laser Texturing
Achieved Groove Depth (H)	110.778 to 117.715	µm	Straight and Wavy Textures
Grinding Wheel Type	Resin-bonded diamond	N/A	SD100 grit size
Grinding Speed (V_s)	30	m/s	Plane Grinding
Workpiece Speed (V_w)	2000	mm/min	Plane Grinding
Grinding Depth (a_p) Range	5, 10, 15, 20	µm	Experimental Range
Max Normal Force Reduction (Wavy)	53.7	%	Compared to Untextured Tools
Max Tangential Force Reduction (Wavy)	51.2	%	Compared to Untextured Tools
Max Surface Roughness Reduction (Wavy)	38.9	%	Compared to Untextured Tools
CFRP Workpiece Material	T800H Carbon Fiber	N/A	Cylindrical Composite Bar
CFRP Turning Feed (f)	0.1	mm/r	Cutting Experiment

Key Methodologies

Substrate Preparation: WC-Co cemented carbide inserts were selected. The back surface of the blade had a 0.4 mm machining allowance.
Laser Surface Texturing (LST): An ultrafast picosecond pulsed laser (BC-2900) was used to ablate two patterns—Straight and Wavy—onto the tool surface. The laser beam was modulated into a flat-top profile for uniform energy distribution and sharp edge creation.
Texture Geometry: Straight and Wavy patterns were designed with groove widths (W) and spacings (W) of approximately 150 µm and a target depth (H) of 120 µm, aligned with the wheel feed direction.
Post-LST Cleaning: Tools were subjected to ultrasonic cleaning in anhydrous ethanol for 10 minutes, followed by nitrogen gas blow-drying.
Grinding Process: Plane grinding tests were performed on a CNC high-precision plane grinder (MGK7120) using a resin-bonded diamond wheel (SD100) in a down-grinding mode.
Cooling Management: A water-based coolant (Type W20) at 3% concentration was supplied continuously at a high flow rate (25 L/min) to the grinding zone.
Force Measurement: Tangential and normal grinding forces were measured using a Kistler 9272 high-precision force gauge system.
Quality Assessment: Surface morphology, surface roughness (S_a), and cutting edge chipping (length and depth) were evaluated using a laser confocal microscope (LEXT OLS5000).
Performance Validation: Turning experiments were conducted on T800H CFRP rods under dry cutting conditions (a_p = 0.3 mm) to compare the resulting CFRP surface quality based on the tool’s edge integrity.

Commercial Applications

The findings directly support the manufacturing and application of high-performance cutting tools, particularly in sectors dealing with difficult-to-machine materials.

Aerospace and Defense: Manufacturing and finishing of tools (e.g., end mills, inserts) used for machining high-value composite materials like CFRP, ensuring minimal fiber pull-out and superior surface finish on the final component.
Precision Tooling Industry: Optimization of the grinding process for cemented carbide and ceramic tools, leading to reduced processing time, lower energy consumption, and extended tool life due to minimized edge defects.
Medical and Micro-Machining: Production of micro-tools requiring extremely sharp, defect-free edges, where conventional grinding often induces unacceptable micro-cracks and chipping.
Hard Material Machining: Application of laser-assisted grinding techniques for tools used in processing hardened steels, titanium alloys (e.g., Ti-6Al-4V), and other high-hardness, low-toughness materials where thermal damage and high grinding forces are problematic.
High-Efficiency Manufacturing: Implementation of LST as a standard pre-treatment step in automated tool production lines to achieve high-efficiency, low-loss tool machining.

View Original Abstract

WC-Co cemented carbide has been widely used as machining tool material due to its good mechanical properties. Grinding is an important process in the manufacture of cemented carbide tools. When grinding tools, there are problems such as excessive grinding force, small chip space, and poor lubrication and cooling performance, which in turn contribute to surface defects such as burrs, burns, and even edge damage such as edge chipping. These problems constrain the use of carbide tools, so that the cutting force is unstable and the machining surface quality is poor when the tool is in service. In this paper, straight-line and wavy-texture patterns were designed and formed on the surface of WC-Co tools using a picosecond laser. Grinding experiments were conducted on the ablated tool using a resin-bonded diamond wheel, and surface morphology, roughness, grinding force, and cutting edge quality were evaluated. Finally, turning experiments were conducted to compare the cutting performance of the tools after conventional and laser-assisted grinding. The experimental results showed that the tools with wavy texture showed superior surface and cutting edge quality, with 53.7% and 51.2% reduction in normal and tangential grinding forces, respectively, and 66.6% maximum reduction in edge chipping for the wavy textured tools. Therefore, this study not only reveals the advantages of laser-assisted grinding in machining WC-Co cutting tools, but also provides a valuable theoretical basis for realizing high-efficiency and low-loss tool machining.

Tech Support

Original Source

DOI: https://doi.org/10.3390/ma18030528

References

2022 - Effect of laser surface texturing on the wettability of WC-Co cutting tools
2020 - Wear mechanism of WC-Co cemented carbide tool in cutting Ti-6Al-4V based on thermodynamics [Crossref]
2020 - Multi-pattern failure modes and wear mechanisms of WC-Co tools in turning Ti-6Al- 4V [Crossref]
2020 - Effect of carbon content on microstructure and mechanical properties of WC-10Co cemented carbides with plate-like WC grain [Crossref]
2020 - Surface roughness profile and its effect on coating adhesion and corrosion protection: A review [Crossref]
2023 - Improved grinding performance of SiC using an innovative bionic vein-like structured grinding wheel optimized by hydrodynamics [Crossref]
2020 - Study on the optical quality and strength of glass edges after the grinding and polishing process [Crossref]
2020 - Surface analysis of WC-5%Co cemented tungsten carbide cutting insert after plunge-face grinding [Crossref]
2015 - Significant influence factors on the grinding tool wear and cutting mechanisms during grinding of PCBN inserts [Crossref]
2021 - Effect of the grinding process on the wear of a cemented tungsten carbide cutting insert during turning [Crossref]