This paper investigates the effect of material type, material thickness, laser wavelength, and laser power on the efficiency of the cutting process for industrial state-of-the-art cutting machines. The cutting efficiency is defined in its most basic terms: as the area of cut edge created per Joule of laser energy. This fundamental measure is useful in producing a direct comparison between the efficiency of fiber and CO2 lasers when cutting any material. It is well known that the efficiency of the laser cutting process generally reduces as the material thickness increases, because conductive losses from the cut zone are higher at the lower speeds associated with thicker section material. However, there is an efficiency dip at the thinnest sections. This paper explains this dip in terms of a change in laser–material interaction at high cutting speeds. Fiber lasers have a higher cutting efficiency at thin sections than their CO2 counterparts, but the efficiency of fiber laser cutting falls faster than that of CO2 lasers as the material thickness increases. This is the result of a number of factors including changes in cut zone absorptivity and kerf width. This paper presents phenomenological explanations for the relative cutting efficiencies of fiber lasers and CO2 lasers and the mechanisms affecting these efficiencies for stainless steels (cut with nitrogen) and mild steel (cut with oxygen or nitrogen) over a range of thicknesses. The paper involves a discussion of both theoretical and practical engineering issues.

References

References
1.
Steen
,
W. M.
, and
Kamalu
,
J. N.
,
1983
, “
Laser Cutting
,”
Laser Material Processing
,
M.
Bass
, ed.,
Elsevier
,
Amsterdam, The Netherlands
, pp.
17
111
.
2.
Yilbas
,
B. S.
, and
Kar
,
A.
,
1998
, “
Thermal and Efficiency Analysis of CO2 Laser Cutting Process
,”
Opt. Lasers Eng.
,
29
(
1
), pp.
17
32
.
3.
Yilbas
,
B. S.
,
2004
, “
Laser Cutting Quality Assessment and Thermal Efficiency Analysis
,”
J. Mater. Process. Technol.
,
155–156
, pp.
2106
2115
.
4.
Niziev
,
V. G.
, and
Nesterov
,
A. V.
,
1999
, “
Influence of Beam Polarization on Laser Cutting Efficiency
,”
J. Phys. D: Appl. Phys.
,
32
(
13
), pp.
1455
1461
.
5.
Wandera
,
C.
, and
Kujanpaa
,
V.
,
2010
, “
Characterization of the Melt Removal Rate in Laser Cutting of Thick-Section Stainless Steel
,”
J. Laser Appl.
,
22
(
2
), pp.
62
70
.
6.
Black
,
I.
,
1999
, “
A Comparison of Severance Energies for Reactive CO2 Laser Cutting of Mild Steel
,”
Int. J. Adv. Manuf. Technol.
,
15
(
11
), pp.
832
834
.
7.
Lütke
,
M.
, and
Hauptmann
,
J.
,
2012
, “
Energetic Efficiency of Remote Cutting in Comparison to Conventional Fusion Cutting
,”
J. Laser Appl.
,
24
(
2
), p.
022007
.
8.
Goppold
,
C.
,
Zenger
,
K.
,
Herwig
,
P.
,
Wetzig
,
A.
,
Mahrle
,
A.
, and
Beyer
,
E.
,
2014
, “
Experimental Analysis for Improvements of Process Efficiency and Cut Edge Quality of Fusion Cutting With 1 μm Laser Radiation
,”
Phys. Procedia
,
56
, pp.
892
900
.
9.
Petring
,
D.
,
2001
, “
Basic Description of Laser Cutting
,”
LIA Handbook of Laser Materials Processing
,
J. F.
Ready
and
D. F.
Farson
, eds.,
Laser Institute of America and Magnolia Publishing
,
Orlando, FL
, pp.
425
433
.
10.
Petring
,
D.
,
Schneider
,
F.
,
Wolf
,
N.
, and
Nazery
,
G. V.
,
2009
, “
How Beam Quality, Power and Wavelength Influence Laser Cutting and Welding Processes
,” 5th International Congress on Laser Advanced Materials Processing, LAMP 2009, Kobe, Japan, Jun 29–Jul 2, pp.
1
8
.
11.
Varga
,
T.
, and
Spörk
,
N.
,
1998
, “
Materials and Workpiece Classification
,”
Handbook of the EuroLaser Academy
,
1st ed.
, Vol.
2
,
D.
Schuocker
, ed.,
Chapman & Hall
,
London
, pp.
146
182
.
12.
Henning
,
T.
, and
Mutschke
,
H.
,
1997
, “
Low-Temperature Infrared Properties of Cosmic Dust Analogues
,”
Astron. Astrophys.
,
327
, pp.
743
754
.
13.
Powell
,
J.
,
Petring
,
D.
,
Kumar
,
R. V.
,
Al-Mashikhi
,
S. O.
,
Kaplan
,
A. F. H.
, and
Voisey
,
K. T.
,
2009
, “
Laser–Oxygen Cutting of Mild Steel: The Thermodynamics of the Oxidation Reaction
,”
J. Phys. D: Appl. Phys.
,
42
(
1
), p.
015504
.
14.
Powell
,
J.
,
Al-Mashikhi
,
S. O.
,
Kaplan
,
A. F. H.
, and
Voisey
,
K. T.
,
2011
, “
Fibre Laser Cutting of Thin Section Mild Steel: An Explanation of the ‘Striation Free’ Effect
,”
Opt. Lasers Eng.
,
49
(
8
), pp.
1069
1075
.
15.
Petring
,
D.
,
Molitor
,
T.
,
Schneider
,
F.
, and
Wolf
,
N.
,
2012
, “
Diagnostics, Modeling and Simulation: Three Keys Towards Mastering the Cutting Process With Fiber, Disk and Diode Lasers
,”
Phys. Procedia
,
39
, pp.
186
196
.
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