Influence of cutting parameters on wear of diamond wire during multi-wire rocking sawing with reciprocating motion

At a Glance

Metadata	Details
Publication Date	2022-08-30
Journal	Frontiers in Mechanical Engineering
Authors	Zixing Yang, Hui Huang, Xinjiang Liao
Institutions	Huaqiao University
Citations	4
Analysis	Full AI Review Included

Executive Summary

This research establishes a theoretical and numerical model to predict and analyze diamond wire saw (DWS) wear during multi-wire rocking sawing (MWRS) of hard-and-brittle materials (e.g., silicon, sapphire).

Modeling Achievement: A theoretical DWS wear model was developed using an iteration method to calculate and superimpose wear across the entire wire length based on the volume of material removed per reciprocating cycle.
Critical Parameters: Workpiece feed speed ($v_s$) and the wire saw setting out length per minute ($L$) were identified as having the most significant impact on the maximum wear experienced by the DWS.
Negligible Parameters: Maximum rocking angle ($\theta$), maximum wire speed ($v_w$), and reciprocating times per minute ($f$) showed little to no effect on the maximum wear magnitude.
Shape Dependence: Workpiece geometry fundamentally dictates the wear profile. Rectangular ingots result in a stable, even wear profile in the middle section, while circular ingots cause highly uneven wear throughout the entire cutting process.
Engineering Value: The simulation provides a predictive tool (flowchart) for optimizing MWRS parameters to minimize DWS consumption, thereby reducing costs and improving the quality consistency of sliced wafers.

Technical Specifications

The following parameters were used in the single-factor numerical simulations to analyze the influence on diamond wire saw wear.

Parameter	Value Range	Unit	Context
Maximum Rocking Angle ($\theta$)	2, 4, 6, 8, 10	°	Simulation variable
Maximum Wire Speed ($v_w$)	10, 15, 20, 25, 30	m/s	Simulation variable
Workpiece Feed Speed ($v_s$)	0.1 to 0.3 (in 0.05 increments)	m/min	Simulation variable
Setting Out Length per Minute ($L$)	8, 12, 16, 20, 24	m/min	Simulation variable
Reciprocating Times per Minute ($f$)	0.4, 0.6, 0.8, 1.0, 1.2	min^-1	Simulation variable
Wire Saw Acceleration ($a$)	4	m/s²	Constant used in cycle time calculation
Model Discretization Accuracy	0.1	m	Length interval for matrix calculation
Rectangular Workpiece Size ($h, l$)	0.2, 0.2	m	Workpiece height and width
Circular Workpiece Radius ($R$)	0.1	m	Workpiece cross-sectional radius
Number of Cut Pieces (Wafers)	100	-	Simulation constant
Wire Spacing ($S_p$)	2	m	Distance between adjacent wafers

Key Methodologies

The wire saw wear model was established and analyzed using a combination of theoretical derivation and iterative numerical simulation.

Theoretical Wear Model Derivation: The wear degree ($S$) of the wire saw was correlated directly to the volume of workpiece material removed ($p$) by the wire saw, using a constant cutting ability coefficient ($k$).
Reciprocating Cycle Analysis: Formulas were established to define the time parameters ($T, t_f, t_b, t_a$) and lengths ($x_1, x_2$) of the wire saw movement during one complete reciprocating cycle, accounting for acceleration, deceleration, and uniform motion stages.
Single Wafer Wear Calculation: The volume of workpiece removed per unit length ($q_{cycle}$) was calculated for each discrete segment of the wire saw during a single cycle. Matrix addition was used to superimpose the wear across the wire length for the entire cutting of one wafer ($S_{location}$).
Multi-Wafer Superposition: An iteration method was implemented to model the continuous process of cutting multiple wafers. The wear profile from each subsequent wafer was calculated and offset along the wire length (due to wire consumption/take-up) and superimposed onto the previous wear profile, generating the cumulative multi-wafer wear matrix ($multiS_{location}$).
Workpiece Geometry Comparison: The model was applied to two distinct geometries:
- Rectangular: Assumed a consistent sawing area, leading to stable wear calculations in the middle phase.
- Circular: Modeled the irregular sawing area, where the contact length changes continuously, resulting in uneven wear.
Numerical Simulation: Single-factor experiments were conducted by systematically varying one cutting parameter (e.g., $v_s$, $L$, $f$, $\theta$, $v_w$) across its range while keeping all other parameters constant to isolate its influence on the maximum DWS wear.

Commercial Applications

This research is directly applicable to industries requiring high-precision slicing of hard crystalline materials, focusing on optimizing tool life and improving wafer quality consistency.

Semiconductor Manufacturing: Essential for slicing silicon (Si) and silicon carbide (SiC) ingots into wafers, where minimizing subsurface damage and maximizing yield are critical.
Photovoltaic (PV) Industry: Used in the high-speed, multi-wire slicing of silicon ingots for solar cell production, where wear optimization directly impacts manufacturing cost.
Advanced Materials Processing: Applicable to the slicing of hard-and-brittle materials like sapphire (used for LED substrates and high-strength windows) and other advanced ceramics.
Digital Manufacturing and Process Control: The developed wear model and simulation framework can be integrated into digital twins or machine control systems to predict tool wear in real-time and automatically adjust feed speed or wire length parameters to maintain optimal cutting performance.
Tool Life Optimization: Provides data necessary for manufacturers of diamond wire saws to design products with improved wear resistance and tailored performance for specific workpiece geometries.

View Original Abstract

Multi-wire cutting with diamond wire saw has gradually become the main processing method for hard-and-brittle materials due to its small kerf loss and high machining accuracy. However, the diamond wire saw will inevitably suffer wear during the process of machining, and hence affects the quality of the cut surface. In this paper, a wire saw wear model was established, and the wear at different positions on the wire saw was theoretically calculated by correlating the volume of the workpiece removed by the unit wire saw to the wire saw wear. The iteration method was used to calculate the wear of the wire saw after cutting by superimposing the wear caused by every monolithic wafer. Based on this wear year model of the wire saw, the influence of multi-wire cutting parameters and the shapes of the workpiece on the wire saw wear was discussed through numerical simulation. The simulation results showed that the feed speed of the workpiece and the length of the wire saw had an obvious effect on the maximum wear of the wire saw, and the maximum rocking angle, wire speed, and reciprocating times had little effect on the maximum wear of the wire saw. The wear curve of the circular workpiece wire saw is unstable in the whole process, and the wear curve of the rectangular workpiece wire saw changes at the beginning and end, and the middle is stable.

Tech Support

Original Source

DOI: https://doi.org/10.3389/fmech.2022.978714

References

2019 - MACE nano-texture process applicable for both single- and multi-crystalline diamond-wire sawn Si solar cells [Crossref]
2016 - Experiment study on electroplated diamond wire saw slicing single-crystal silicon [Crossref]
2016 - Theoretical research on contact length in the rocking motion wire saw [Crossref]
2015 - Effect of initial deflection of diamond wire on thickness variation of sapphire wafer in multi-wire saw [Crossref]
2013 - Multi-wire sawing of sapphire crystals with reciprocating motion of electroplated diamond wires [Crossref]
2018 - Investigation of the progressive wear of individual diamond grains in wire used to cut monocrystalline silicon [Crossref]
2016 - Effect of wear of diamond wire on surface morphology, roughness and subsurface damage of silicon wafers [Crossref]
2016 - Investigation on diamond wire break-in and its effects on cutting performance in multi-wire sawing [Crossref]
2015 - Slicing parameters optimizing and experiments based on constant wire wear loss model in multi-wire saw [Crossref]
2022 - Experimental investigation on diamond wire sawing of Si3N4 ceramics considering the evolution of wire cutting performance [Crossref]