Front Cover

The Laser Cutting Process: Analysis and Applications

Copyright

Dedication

Contents

Preface

Chapter 1: Introduction

References

Chapter 2: Thermal analysis of the laser cutting process

2.1. Introduction

2.2. Absorption of laser beam intensity

2.3. Temperature and stress fields in relation to key-hole formation

2.3.1. Exponential pulse heating and evaporation at the surface

2.3.2. Thermal stress analysis

2.4. Jet impingement and flow field in the key-hole

2.4.1. Flow equations

2.4.2. Flow boundary conditions

2.4.2.1. Solid wall

2.4.2.2. Generalized wall functions for normal and shear turbulent stresses for the RSM model

2.4.2.3. Inlet conditions

2.4.2.4. Outlet

2.4.2.5. Symmetry axis

2.4.3. Solid side

2.4.3.1. Constant wall temperature boundary

2.4.3.2. Solid fluid interface

2.4.3.3. Solid heating

2.4.3.4. Working fluid and solid

2.4.4. Numerical method and simulation

References

Chapter 3: Analytical methods in laser cutting

3.1. Introduction

3.2. Pulse heating analysis of solid surfaces in relation to initiation of laser cutting

3.3. Laser solid-phase heating and convection cooling at the surface resembling assisting gas effect

3.4. The thermal stress field generated due to the convection boundary at the surface

3.5. Two-dimensional heating

3.6. Transient evaporation

3.7. Three-dimensional heating and stationary source at the surface

3.8. Laser cutting process and striation formation

3.9. Lump parameter analysis for kerf width formulation

3.10. Analytical assessment of assisting gas

3.10.1. Laminar boundary layer consideration

3.10.1.1. Frozen boundary layer approximations

3.10.1.2. Boundary layer heat transfer

3.10.1.3. Heat transfer to the liquid metal

3.10.2. Turbulence boundary layer consideration

3.10.2.1. Boundary layer heat transfer

3.10.2.2. Heat transfer to the liquid undersurface

3.10.2.3. Method of solution

3.10.2.3.1. Chemical enthalpy potential hc

3.10.2.3.2. Species mass fractions

3.10.2.3.3. Mass-transfer parameter B2

3.10.2.3.4. Determination of value of CHd/CHc

3.10.2.4. Findings of turbulent boundary treatment

3.11. Analysis of dross formation during cutting

3.11.1. Formulation of liquid layer thickness and velocity

3.11.2. Dross formation

3.11.3. Findings of dross ejection

References

Chapter 4: Laser cutting quality assessment and numerical methods for modeling of cutting

4.1. Introduction

4.2. Striation pattern assessments

4.3. Factorial analysis for laser cutting quality assessments

4.3.1. Qualitative analysis

4.3.2. Quantitative analysis

4.3.3. Evaluation of cut quality

4.4. Numerical investigation of the laser cutting process

4.4.1. Heating analysis

4.4.2. Thermal stress analysis

4.4.3. Numerical solution

4.5. Three-dimensional heating considerations for laser cutting

4.5.1. Mathematical formulation of the heating situation

4.5.1.1. Turbulence modeling

4.5.1.2. Flow boundary conditions

4.5.1.2.1. Solid wall

4.5.1.2.2. Inlet conditions

4.5.1.2.3. Outlet conditions

4.5.1.3. Solid side

4.5.1.3.1. Constant wall temperature boundary

4.5.1.3.2. Solid fluid interface

4.5.2. Numerical method and simulation

4.5.3. Case studies on impinging gas jet effects on kerf sites

4.5.3.1. Effect of kerf wedge angle on heat transfer rates and skin friction

4.5.3.2. Influence of kerf thickness on heat transfer and skin friction

4.5.3.3. Influence of assisting gas type on the Nusselt number and skin friction

4.5.3.4. Effect of jet velocity on heat transfer rates

4.6. Entropy analysis of the laser cutting process

References

Chapter 5: Some applications of laser cutting

5.1. Introduction

5.2. Heating and stress analysis

5.2.1. Thermal analysis

5.2.2. Thermal stress analysis

5.3. Numerical simulations

5.4. Laser high-thermal conductive materials

5.4.1. Straight laser cutting of bronze

5.4.2. Laser circular cutting of bronze

5.5. Laser cutting of high-elastic modules and materials

5.5.1. Laser straight cutting of alumina tiles

5.5.2. Circular laser cutting of alumina tiles

5.5.3. Rectangular laser cutting of alumina tiles

5.5.4. Laser cutting of aluminum foam

5.5.4.1. Laser straight cutting of aluminum foam

5.5.4.2. Laser circular cutting of aluminum foam

5.5.4.3. Laser triangular cutting of aluminum foam

5.5.5. Laser cutting of Kevlar

5.5.6. Laser cutting of a carbon/carbon multilamelled plain-weave structure

5.5.7. Wedge cutting of mild steel

5.5.8. Laser cutting of titanium alloy

5.5.8.1. Laser straight cutting of titanium alloy

5.5.8.2. Laser circular cutting of titanium alloy

References

Chapter 6: Concluding remarks

6.1. Analytical treatment of the laser cutting process

6.2. Numerical analysis associated with laser cutting

6.3. Laser cutting of difficult-to-cut materials

6.3.1. Laser cutting of bronze

6.3.2. Laser cutting of alumina tiles

6.3.3. Laser cutting of aluminum foam

6.4. Laser cutting of Kevlar

6.5. Laser cutting of composites

6.6. Laser cutting of wedges in steel

Index

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