C
laser applications in body shop,
558–65
Carman–Kozeny equation,
539
charge-coupled device (CCD),
96
transmission laser welding,
295
BPP of some lasers as a function of laser output power,
21
CO
2 laser beam characteristics,
19–22
fibre optical rotary joints (FORJ) for optical fibre,
313–15
industrial applications,
39–44
automotive industry,
39–40
laser welded sandwich panel,
42
laser welded tailored blanks,
40
riveting vs laser welding for the skin to stringer joint,
41
shipbuilding industry,
41–2
keyhole welding process,
307–10
laser–materials interactions,
22–31
phenomena and defects,
31–9
CO
2 laser welds without back shielding,
37
defect formation in partial penetration,
33–6
defect formation in single pass full penetration,
36–9
hot cracking formation,
38
in-situ x-ray transmission image near the keyhole tip,
35
in-situ x-ray transmission image of keyhole,
34
porosity formation ratio Pr as a function of power modulation frequency,
36
pressure balance on keyhole wall,
31–3
prevention of porosity under optimum power modulation condition,
36
single pass full penetration CO
2 laser welding behaviour of C–Si–Mn steel,
37
principles and types,
17–19
transverse flow laser,
19
spot welding for optical assembly,
310–13
laser and sensor positioning,
413
sensor positioning and profile,
412
combined laser beam welding
combining laser welding and laser cutting,
493–502
computed deformation of plate after forming by CO
2 laser, Plate XIII
laser and arc hybrid welding,
480–92
map of combined laser processes and tools, Plate XXIII
conduction laser welding,
139–57
high power diode laser,
154
kitchen sink weld and powder deposition,
154
laser filler weld seams on titanium,
155
manufacturing of a 3D block of a Ti–47Al–2Cr–2Nb and Cp–Ti tube,
156
sample in AA6083 with different power and welding speeds,
153
underwater laser beam welding and deposit,
157
welded AZ61 magnesium alloy,
155
conduction and keyhole mode transition,
142–7
identification of the different welding regimes,
145
identification of three welding modes,
146
laser power density necessary to reach vaporisation temperature,
143
three welding modes by Buvanashekaran,
148
three welding regimes,
147
variation of penetration, for aluminium, with the power density and pulse time,
144
variation of surface temperature and the penetration with beam radius in aluminium,
149
advantages and disadvantages,
141
blowout event that originates spatter,
140
conduction laser weld with 6.35 mm of penetration,
141
conservation of energy,
107
conservation of mass,
106
conservation of momentum,
106
conservation of species,
107
continuous wave laser, ,
304–15
CO
2 laser welding applications,
307–15
different welding modes,
304
residual stress in melting containing free surface,
305–7
continuous wave laser welding
laser welding developments,
119–31
covariance mapping technique (CMT),
220
effect of beam intensity ratio on change in stress intensity,
456
experimental vs analytical results of crack path for single-laser beam,
455
schematic illustration of laser cutting,
454
tandem-beam irradiation in laser cutting of glass,
456
D
deep penetration welds,
11,
13
defocusing distance,
581–2
influence on penetration depth of overlap joint,
582
hybrid laser welding with high laser power,
97–100
laser metal deposition (LMD) by powder injection,
84–9
laser scanner welding,
89–93
powertrain production,
93–7
cavity of a disk laser setup,
74
laser power extraction per unit of area,
76
output power and efficiency of a typical high power single disk laser oscillator,
76
technological trends and developments,
77–8
dissimilar-material joint,
255
formation and properties,
268–75
bend test of laser MIG hybrid welded aluminium–steel sheets,
275
effect of heat input per length on phase seam thickness,
272
fractured laser MIG hybrid welded aluminium steel specimen,
274
grains orientation of a typical phase layer in aluminium steel joints,
271
joint formation and the intermetallic phase layer,
268–72
laser power effect on layer thickness of MIG hybrid welding of aluminium to steel,
271
mechanical properties and formability,
272–5
phase layer in aluminium steel joints,
270
relation between wetting length and tensile length,
273
titanium–aluminium aircraft seat tracks,
268
zinc-rich region at the tip of the wetted zone,
269
principle design approach for integral CFRP–aluminium structure,
276
intermetallic phase properties for binary system Fe-Al,
258
laser joining processes,
259–68
aluminium–steel tailored hybrid blank,
267
aluminium–steel tailored hybrid tube,
267
aluminium–titanium joining process principle,
261
aluminium–titanium joint surface and cross section,
262
combined and special processes,
262–6
general considerations,
259
laser MIG hybrid welded aluminium–steel specimen,
265
laser MIIG hybrid joining process,
264
laser-plasma hybrid joining,
266
laser welding of aluminium to steel,
261
potential application,
266–8
process parameter envelope for laser MIG hybrid welding,
265
research activities in the field of laser joining,
260
superimposed force-effect of force,
263
superimposed force-process principle,
263
laser welding and brazing,
255–76
longitudinal and transverse shrinkage,
380–5
L
advanced technical equipment
principle and practical device of the integrated hybrid welding nozzle,
487
orbital welding equipment with laser arc hybrid weld head,
513
heavy section high-strength steel plates,
488–92
CO
2-laser-MAG hybrid welding parameters,
492
distance influence between laser and arc with an optimum for weld efficiency,
488
expanded process windows and improved gap bridging,
490
fatigue results of heavy section laser hybrid welds,
492
focal position influence with an optimum for weld efficiency,
489
hybrid welded high-strength steel plates cross section,
491
process windows and gap bridging capability for laser-MAG hybrid welding,
490
optics with scanner module,
509
physical model of root formation,
484–6
hybrid welding of fillet weld at lap joint,
484
root pressure balance,
485
three different cases for the gap bridging capability,
486
principle and state-of-the-art,
480–4
gap bridging capability in an aluminium alloy,
484
parameters showing benefits of hybrid welding,
483
element distribution (Ni, Cr) in laser-hybrid weld of S690 steel,
517
hardness distribution in laser-hybrid welded X65 steel,
516
hot crack susceptibility for S690 with increasing restraint intensity,
515
technology development,
505–19
temperature distribution,
543
laser-assisted metal and plastic (LAMP),
208–9
output waveform with relaxation pulse,
178
Gaussian beam profile weld,
180
Nd:YAG pulsed laser beam profile,
178
single-mode fibre laser beam profile,
180
top hat (flat top) beam profile of 300 W fibre laser,
181
top hat welds at different pulse energies,
179
Gaussian beam width as a function of the axial distance,
166
vs laser output power,
166
beam movement over the workpiece,
424–6
large-scale remote welding system,
427
stand-alone system of large-scale remote welding station,
427
superposition of scanning head with linear axes for welding of large-scale 2D parts,
426
superposition of scanning head with robot for welding large scale 3D parts,
425
typical 2D-and 3D-part welded,
428
welding seam of automotive heat exchanger,
425
combining two different scanning heads to provide beam shaping,
432
beam deflection by using scanning mirrors,
423
technology developments,
422–32
dendritic structure of overlap laser welding joints,
584
microstructure of overlap laser welding joints,
583
formation and properties,
268–75
laser joining processes,
259–68
mixed-material design in the automotive industry,
256
cutting heads vs welding heads,
494
scheme and principle of the autonomous nozzle and combi-head, Plate XXIV
combining with laser welding,
493–502
case studies of combined laser cutting and welding,
499
combi-processed B-pillar,
500
cutting and welding speeds vs thickness,
499
integrated process chain for nonlinear tailored blank production,
497
multifunctional processing,
493–4
sealed overlap drill hole production by laser cutting,
502
solutions and applications,
496–8
laser-diode (LD)-pumped solid-state (YAG) laser,
5–6
laser-induced plasma,
23–31
incident laser energy attenuation by inverse Bremsstrahlung,
23–7
absorptivity of some materials for three wavelengths at room temperatures,
22
computed deformation of plate after forming by CO
2 laser, Plate XIII
mechanism by micro shockwave,
396
laser-gas metal arc (GMA) welding,
121,
545
laser-gas tungsten arc (GTA) welding,
121
incident laser energy attenuation by inverse Bremsstrahlung,
23–7
laser power effect on plasma size and absorptivity,
29
maximum plasma temperature, plasma size and absorptivity for argon shielding gas,
30
maximum plasma temperature, plasma size and absorptivity for defocus distances,
31
temperature profile of argon plasma,
28
in-process monitoring of penetration depth by plasma emission signal,
32
radiative heat transfer,
114–15
transport phenomena,
107–8
laser-induced recoil pressure,
108–11
gas dynamic of vapour and air,
109
laser–materials interactions,
22–31
laser energy absorption in laser-induced plasma,
23–31
laser energy absorption on material surface,
22–3
laser metal deposition (LMD)
coating production on agricultural cutting discs,
86
piston ring groove after laser metal deposition and machining,
87–9
transfer of deposit material,
85
laser welded radioactive isotopes,
206
laser welding of microwave packages and a drop-in cover,
207
seam weld around the cardiac pacemaker,
206
defects and joints evaluation,
194–202
effect of weld diameter on the nugget size and shear strength,
202
absorptivity vs wavelength of different metals,
184
conduction mode laser welding,
183
dissimilar weld joints,
193
four different alloy additions on the crack sensitivity of aluminium,
188
keyhole or deep penetration mode laser welding,
185
maximum gap and positioning tolerances for different laser welded joints,
187
microwelding of dissimilar materials,
191–2
minimum laser power needed to melt different metals pulsed Nd:YAG laser,
184
plating and coatings,
192–4
ramp down temporal laser pulse shape,
194
shielding gas during welding,
182
weldability of metal pairs,
191
welds made with 400 W (JK400FL) single-mode fibre laser,
186
laser-plasma interaction,
111–14
laser-plasma welding,
121
Gaussian-like distribution of the intensity of laser beam,
578
influence on penetration of depth of overlap joint,
577
microstructure of the cross section of overlap joint,
578
laser remote welding,
558
laser scanner welding,
89–93
laser remote welded car seat,
93
laser remote welding in body in white,
93
programmable focusing optics (PFO) 3D,
91
rapid welding sequence performed by the programmable focusing optics (PFO),
92
laser surface melting (LSM),
231
laser tool calibration,
408–11
aluminium and titanium alloys,
215–47
applications for improving technique and quality,
546–9
calculated and experimental fusion zone profile, Plate XXIX
calculated temperature profiles and flow patterns in a cross-sectional front view, Plate XXVIII
experimental results in transverse and longitudinal cross sections, Plate XXXII
simulation results in longitudinal cross sections during hybrid welding, Plate XXX
simulation results in transverse and longitudinal cross after solidification, Plate XXXI
temperature profiles, flow patterns and cross sectional side view, Plate XXVII
applications in shipbuilding industry,
596–611
industrial examples,
604–7
production targets and challenges,
555–8
power densities, heat sources and geometries,
combining with laser cutting,
493–502
case studies of combined laser cutting and welding,
499
combi-processed B-pillar,
500
cutting and welding speeds vs thickness,
499
integrated process chain for nonlinear tailored blank production,
497
multifunctional processing,
493–4
sealed overlap drill hole production by laser cutting,
502
solutions and applications,
496–8
defect formation and preventive procedures,
332–69
formation and properties,
268–75
laser joining processes,
259–68
mixed-material design in the automotive industry,
256
laser lap joints of 3 mm thick Type 304 steel plate,
15
laser welds in Type 304 steel,
14
near joint interface between Type 304 steel plate and PET plastic sheet,
15
geometrical or appearance defects,
333,
336–41
burn-through or melt down,
337–9
deformation or distortion,
333,
336
poor surface appearance,
336–7
continuous wave (CW) laser,
304–15
ultra short pulse lasers (USPL),
315–27
hot cracking solidification and liquation cracking formation and prevention,
361,
364–9
alloying element and content on hot cracking susceptibility of welds in aluminium alloys,
368
cracking formation in laser weld fusion zones,
367
effects of various factors on solidification cracking susceptibility of laser welds,
369
partial-penetration and full-penetration welds,
366
spot welds made with pulsed lasers,
365
strain levels applied at constant strain rate for ductility curve,
364
internal or invisible effects,
341,
343–8
alloying elements evaporation loss,
346
hot cracking solidification cracking and liquation cracking,
341,
343
incomplete penetration and fusion,
345–6
key issues in modelling,
524–46
absorptivity vs incident angle based on Fresnel reflection and Drude theory,
527
absorptivity vs incident angle based on Fresnel reflection and Hagen-Rubens relation,
528
diffracted laser beam and direction vector of a ray,
531
laser-arc interaction,
542–4
laser heat source model,
528–31
laser-matter interaction,
524–8
modelling of arc welding process,
544–5
multiple-reflection model of keyhole,
531–5
optical geometry of laser beam,
530
scattering model of keyhole,
535–8
schematic diagram of incoming bundles of rays,
529
schematic diagram of original mesh and sub-mesh,
530
kinds, features, causes and suppression or prevention of main laser welding defects,
334–5
CO
2 and YAG laser welding systems,
remote welding system using solidstate laser,
types and characteristics,
penetration and defects,
11,
13
beam diameter (power density) and welding speed,
13
coupling coefficient of laser energy,
induced plume and gas plasma during CO
2
melt flows in molten pool and weld bead geometry,
12
plume and plasma formation during laser welding,
11
advantages and disadvantages of transmission laser welding,
298–9
polymer combinations,
289
porosity formation and prevention,
351–61
quality of property defects,
348–51
chemical property degradation,
349,
351
mechanical property reduction,
348–9
tensile test results of base metals and welded joints,
350
heat source model of lap laser welding,
585–90
quality control of laser welding joints,
590–2
stainless steel railway vehicles,
576–85
residual stress and distortion,
374–97
longitudinal and transverse shrinkage,
380–5
welding residual stress distribution,
375
connection topology,
403–4
coordinate frames and transformations,
404–6
seam teaching and tracking,
414–15
trajectory-based control,
415–18
diagram of regions for heat transfer calculation,
541
laser welding deformation,
333,
336
laser welding distortion,
333,
336
laser–material interaction,
150
sample in laser weld fusion zone,
343
liquid–solid interface,
117
longitudinal residual stress distribution,
388
P
temporal laser pulse,
171
phase layer formation,
258
Planck mean absorption coefficient,
114–15
plasma arc welding (PAW),
122
advantages and disadvantages of transmission laser welding,
298–9
polymer combinations,
289
compatibility of welding performance between different thermoplastic materials,
290
polymer welding showing chain interdiffusion at a joint,
287
temperature for a laser welded specimen resulting from finite element analysis, Plate XI
welding parameters,
297–8
welding parameters effect,
285
equipment and variations,
292
equipment manipulation,
293–5
laser types for transmission laser welding,
292–3
monitoring and control methods,
296–7
transmission laser welding,
291
mechanical heat source,
288
mechanical movement generated by heat,
287–8
diffusion by reptation,
283–5
graph of specific volume vs temperature for amorphous thermoplastic,
282
graph of specific volume vs temperature for semicrystalline thermoplastic,
282
materials and thermal effects,
281–3
polymer chains crossing an interface by diffusion,
284
polygonal ferrite (PF),
584
effect of depth-to-width ratio of the keyhole, Plate IV
formation and prevention,
351–61
during bead welding with CW laser,
353,
355–9
during spot welding with pulsed laser,
351–3
during welding of materials with great sensitivity,
360–1
effect of defocused distance and pulse width on penetration depths of spot welds,
352
laser welding phenomena,
358–9
laser welds produced at 1–5 mm/s under pulse-modulation conditions,
362
microfocused X-ray transmission
in-situ imaging,
351
phenomena during laser welding of Zn-coated steel lap sheets,
363
porosity in laser weld fusion zone of die-cast AZ91 magnesium alloy,
360
saw-like pulse waves and surface appearances of spot welds,
354
typical and root porosity in spot welds of stainless steel,
353
various types of porosity in laser weld fusion zones,
355
weld beads and X-ray transmission
in-situ imaging,
356
X-ray transmission apparatus,
351
post-weld heat treatment (PWHT),
228,
238,
245
laser welded dual clutch,
95
laser welding of a truck differential gear,
94
TRUMPF TruDisk cavity,
96
preliminary treatments,
566–9
pre-treatment of zinc-coated metal sheets,
567–9
controlled zinc expansion,
568
uncontrolled zinc expansion,
567
surface cleaning of aluminium metal sheets,
566–7
programmable focusing optics (PFO),
89–90
laser welding for porosity prevention,
125–7
effect of pulse control on keyhole collapse and porosity prevention, Plate VII
keyhole collapse and porosity elimination, Plate VI
welding speed vs repetition rate,
171
welding speed vs repetition rate,
171
pulsed Nd:YAG lasers,
79–80
pulsed wave laser welding
free surfaces tracking,
115
keyhole collapse and porosity formation,
118–19
laser-induced recoil pressure and keyhole formation,
108–11
laser-plasma interaction and multiple reflections of laser beam in keyhole,
111–14
melt flow and weld pool dynamics,
115–17
pulsed laser keyhole welding process,
105
radiative heat transfer in laser-induced plasma,
114–15
transport phenomena in laser-induced plasma,
107–8
transport phenomena in metal,
106–7
laser welding developments,
119–31
S
fitted to delivery fibre from the laser,
176
spot welds made with pulsed Nd:YAG laser,
177
interaction between electromagnetic waves and spherical particles,
536
sensor-guided robotic laser welding system,
407
shear tensile tests,
583–4
heat conduction-welded top plate,
84
laser-welded sandwich component for use in medical engineering,
85
sheet metal process chain,
81
TruLaser Robot 5020 robot system,
83
applications of laser welding,
596–611
arc welded panels for a passenger ship,
597
Charpy transition curve for the 0.5 mm gap weld,
602
four-point bending test,
603
hardness profiles for welds,
601
mechanical properties,
600–2
solidification flaws,
600
unified guidelines,
602–4
industrial examples,
604–7
cruise ship built at Aker Yard,
604
Odense Steel Shipyard,
607
KH opening stabilisation,
56–8
melt pool behaviour and KH aperture,
58
simulation, laser processes,
572–3
simultaneous welding,
294
KH with surrounding melt pool,
63
beam movement over the workpiece,
424–6
beam deflection by using scanning mirrors,
423
technology developments,
422–32
laser welding in keyhole (KH) mode,
48–61
computed keyhole profiles,
55
opening stabilisation using side gas jet,
56–8
vapour plume behaviour,
58–60
wall inclination and depth,
48–53
welding under vacuum conditions,
60–1
solidification cracking,
341,
343
sample in laser weld fusion zone,
343
solidification flaws,
600
bare gold-coated laser-welded rooftop,
312
thick plates by CO
2 laser,
311
stainless steel railway vehicles,
576–85
features of laser welding joints,
582–5
mechanical properties,
583–5
microstructure of laser beam welds,
582–3
heat source model of lap laser welding,
585–90
combination of heat source models,
588
cross-section of laser gap weld,
587
simulated pool shapes for different laser power,
589
simulated pool shapes for different welding speeds,
590
simulation vs experiment of molten pool,
589
thermal conductivity and specific heat coefficient,
587
quality control of laser welding joints,
590–2
schematic diagram of joint arrangement,
591
side view of Audi A4,
559
installation, laser head, source and MAG power supply,
609
surface modification,
450–3
appearance of cladding surface,
452
cross-sectional observations of cladded specimen Plate XX
schematic illustration of laser cladding experiment,
451
SEM and Si distribution at molten zone, Plate XXI
Si distribution, Plate XXII
surface tension model,
540
relative physical properties,
587
W
corresponding velocity distribution,
116
pulsed laser welding process, Plate I
high power density and low welding speed combination,
199
rapid closing of the keyhole,
199
root of the weld between aluminium alloy and pure copper,
200
high power density and low welding speed combination,
199
rapid closing of the keyhole,
199
root of the weld between aluminium alloy and pure copper,
200
cross sectional observation of AZ31/ A5052 dissimilar materials, Plate XIX, Plate XVIII
effect of configuration on failure load and strength,
449
effect of configuration on width and penetration depth,
448
failure load of A5052/AZ31,
450
welding and configuration in A5052/Z31,
448
welding configuration in A5052/ AZ31,
450
multi-pass laser welding,
461–2
instability of weld bead shape,
462
results of root pass welding,
463
configurations of twin beam irradiation,
444
cross section of weld bead,
442,
443
effect in high reflective, high thermal and low thermal conductive material,
443
effect of beam distance on porosity formation,
445
effect of configuration on gap tolerance,
445
effect of filler wire on gap tolerance,
446
increasing gap tolerance from changing irradiation point,
446
laser lap welding by tandem twin-beam laser,
446
Q-switched YAG laser and a pulsed YAG laser,
441
schematic illustration of porosity formation,
445
bead shape, crack and microstructure of deposited weld,
467
chemical compositions of base metal and welding wires,
466
effect of welding conditions and wire compositions,
467
pulsed laser welding of 6061 aluminium alloy,
196–7
welding deformation,
378–9
longitudinal and transverse direction,
382–5
temperature distribution and restraint in transverse direction,
384
temperature distribution and restraint in welding direction,
383
transient temperature distribution during butt welding,
383
welding distortion,
391–2
effectiveness of multi-beam laser welding to reduce distortions,
392
welding condition on residual stress and distortion,
391
welding set-up with one laser beam,
392
influence on area of fusion zone,
579
influence on area of surface quality,
580
variation on global behaviour of keyhole (KH) and melt pool,
61–7
different regimes respectively labelled R, S, E, P, H,
66
transition thresholds,
65–7
welding speeds below 5 m/min,
61–2
welding speeds between 6 and 8 m/min,
62–4
welding speeds between 9 and 11 m/min,
64
welding speeds between 12 and 19 m/min,
64–5
welding speeds between 20 m/min,
65