Influence of the Characteristics of a Workpiece on the Slicing Characteristics Including Tool Wear

At a Glance

Metadata	Details
Publication Date	2018-01-01
Journal	MATEC Web of Conferences
Authors	Satoshi Sakamoto, Masaya Gemma, Yasuo Kondo, Kenji Yamaguchi, Mitsugu Yamaguchi
Institutions	Yokohama National University, Yamagata University
Citations	4
Analysis	Full AI Review Included

Technical Documentation & Analysis: Precision Slicing of Hard Materials

This document analyzes the findings of “Influence of the Characteristics of a Workpiece on the Slicing Characteristics Including Tool Wear” and connects the requirements for processing ultra-hard materials to the advanced capabilities offered by 6CCVD (6ccvd.com), a global leader in MPCVD diamond solutions.

Executive Summary

This study provides critical insights into the relationship between workpiece mechanical properties (hardness and toughness) and the performance metrics of diamond multi-wire sawing, directly informing the processing requirements for advanced 6CCVD diamond materials.

Hardness vs. Slicing Time: Higher hardness and toughness (e.g., Sapphire, 23.0 GPa) significantly increase the required slicing time and accelerate diamond wire tool wear.
Accuracy Driver: Workpiece brittleness was found to adversely affect wafer thickness variation more than absolute hardness.
Toughness for Precision: Sapphire, possessing the highest toughness (2.1 MPa), exhibited the smallest wafer thickness variation, demonstrating that high toughness suppresses microfracture and wire wandering, leading to superior slicing accuracy.
Tool Wear: Significant abrasive fall-off and core wire damage were observed when slicing the hardest, toughest material (Sapphire), emphasizing the need for robust, high-quality diamond tools.
Chipping Control: The frequency of chipping depends primarily on workpiece hardness, while the size of chipping depends on workpiece toughness.
Methodology: Experiments utilized a diamond electrodeposited wire tool (143 µm OD, 20-30 µm grain size) running at 100 m/min with a fixed feed rate of 0.8 mm/min.

Technical Specifications

The following hard data points were extracted from the experimental setup and material characterization:

Parameter	Value	Unit	Context
Wire Core Diameter	100	µm	Diamond electrodeposited wire tool
Wire Outer Diameter	143	µm	Diamond electrodeposited wire tool
Abrasive Grain Size	20-30	µm	Diamond
Wire Running Speed	100	m/min	Reciprocating multi-wire saw
Wire Tension	14.6	N	Constant tension setting
Workpiece Feed Speed	0.8	mm/min	Constant feed rate
Coolant Supply Rate	50	mL/min	Glycol-based water-soluble fluid
Sapphire Vickers Hardness	23.0	GPa	Highest hardness tested
Sapphire Fracture Toughness	2.1	MPa	Highest toughness tested
TEMPAX Slicing Time	~20	min	Shortest time (Lowest H/T)
Sapphire Slicing Time	~50	min	Longest time (Highest H/T)
Chipping Measurement Threshold	1.50	µm	Minimum size measured for analysis

Key Methodologies

The experimental investigation focused on controlled slicing parameters to isolate the influence of workpiece mechanical properties:

Apparatus: A wire reciprocating type multi-wire saw was used, controlling feeding and rewinding via a single drum.
Tool Specifications: A diamond electrodeposited wire tool was employed, featuring a 100 µm core diameter, 143 µm outer diameter, and a diamond grain size of 20-30 µm.
Workpieces: Four materials were tested: Borosilicate glass (TEMPAX), Single Crystal Silicon (Mono-Si), Polycrystalline Silicon (Poly-Si), and Sapphire. All samples were 20 mm x 20 mm x 5 mm.
Kinematics: The wire running speed was fixed at 100 m/min, and the workpiece feed speed was fixed at 0.8 mm/min.
Fluid Management: A glycol-based water-soluble coolant was supplied at a rate of 50 mL/min.
Characterization: Slicing time, wafer thickness variation (measured at 11 points), surface quality (SEM), and tool wear (abrasive fall-off and core damage) were measured and correlated with Vickers hardness and fracture toughness values.

6CCVD Solutions & Capabilities

The research confirms that slicing ultra-hard, high-toughness materials like sapphire requires optimized processing and results in significant tool wear. As the manufacturer of the hardest material known (Diamond, > 90 GPa Vickers Hardness), 6CCVD provides the necessary SCD and PCD substrates and engineering expertise required for successful precision processing.

Applicable Materials for Hard Material Processing

To replicate or extend this research—especially when moving to the ultimate hard material, diamond—6CCVD offers materials optimized for demanding slicing and subsequent device fabrication:

6CCVD Material	Application Relevance	Key Specification
Optical Grade SCD	Substrates for high-precision optical windows, quantum computing, or high-power electronics. Requires ultra-low damage slicing.	Thickness: 0.1 µm to 500 µm. Polishing: Ra < 1 nm.
Electronic Grade PCD	Large-area heat spreaders or mechanical components where high hardness and large dimensions (up to 125mm) are critical.	Custom Dimensions: Plates/wafers up to 125 mm. Polishing: Ra < 5 nm (Inch-size).
Heavy Boron Doped Diamond (BDD)	Potential use in advanced electrodeposited wire tools or wear-resistant components, leveraging BDD’s conductivity and extreme hardness for enhanced tool life.	Thickness: Up to 500 µm. Available as wafers or custom shapes.

Customization Potential for Advanced Slicing Projects

The study highlights the challenge of achieving low thickness variation and minimizing chipping size in hard materials. 6CCVD’s in-house capabilities ensure that the starting material is optimized for subsequent precision processing:

Custom Dimensions: While the paper used 20 mm x 20 mm samples, 6CCVD routinely supplies custom plates and wafers up to 125 mm in diameter (PCD) and large-area SCD, accommodating industrial-scale slicing requirements.
Ultra-Precision Polishing: The study noted that high toughness reduces surface damage. 6CCVD guarantees Ra < 1 nm for SCD, providing a superior starting surface that minimizes the need for aggressive post-slicing lapping and polishing.
Integrated Metalization: For applications where the sliced wafer requires subsequent device integration (e.g., electrodes or contacts), 6CCVD offers internal metalization services including Au, Pt, Pd, Ti, W, and Cu layers, applied directly to the SCD or PCD surface.
Substrate Thickness Control: We offer SCD and PCD substrates in precise thicknesses ranging from 0.1 µm to 500 µm, ensuring engineers can select the optimal starting material thickness to minimize waste during the high-wear slicing process.

Engineering Support

The relationship between hardness, toughness, and slicing parameters is complex. 6CCVD’s in-house PhD team specializes in the mechanical and physical properties of CVD diamond. We offer consultation services to assist engineers and scientists in optimizing material selection and processing recipes for similar hard material slicing and processing projects, ensuring maximum yield and minimal tool wear.

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

View Original Abstract

Multi-wire saws with a diamond electrodeposited wire tool are widely used to slice hard and brittle materials. The properties of the materials significantly affect the saw’s performance in terms of slicing quality, efficiency, and accuracy. In this study, the effects of the material properties of workpieces on wire tool performance and tool wear are described. The main conclusions are as follows: the higher the hardness and toughness of the workpiece material, the longer the slicing time and greater the damage to the wire tool. The brittleness of the workpiece adversely affects the thickness variation more than its hardness. In addition, the frequency of chipping mainly depends on the hardness of the workpiece, whereas the chipping size mainly depends on the toughness of the workpiece.

Tech Support

Original Source

DOI: https://doi.org/10.1051/matecconf/201822104005