46
Laserline GmbH, Germany 1 Metal Welding Metal Welding with Diode Lasers with Diode Lasers June 2005 June 2005 Laserline GmbH ! Mülheim-Kärlich ! Germany www.laserline.de
Laserline GmbH, Germany 1
Metal WeldingMetal Welding
with Diode Lasers with Diode Lasers
June 2005June 2005
Laserline GmbH ! Mülheim-Kärlich !
Germany
www.laserline.de
Laserline GmbH, Germany 2
Metal Metal WeldingWelding withwith Diode Laser Diode Laser
Direct diode laser on robot. Photo: Irepa, France
Advantages of Diode Lasers
High welding speeds
Smooth and even welds that are free from
pores and cavities
Ideal working distance
Less weld seam after-treatment
Applications
Sheets and foils, automotive industry,
consumer goods, boxes and housings, fine-
and spot welding
Laserline GmbH, Germany 3
Metal Welding: Typical DataMetal Welding: Typical Data
Laser
Direct and fiber-coupled diode lasers
Power
90 W to 4000 W
Beam quality
40 - 150 mm mrad
Spot dimensions
0.4 to 1.5 mm
Material
- Stainless and other types of steel,
aluminum, others
- Thickness: 0.1 – 2.5 mm
Stainless steel kitchen sink
10
100
1000
10 100 1000 10000
Power [W]
Be
am
qu
ali
ty [
mm
mra
d]
Hartlöten
Schneiden Tiefschweißen
Schweißen
Hybridschweißen
Härten
Auftragsschweißen
10
100
1000
10 100 1000 10000
Power [W]
Be
am
qu
ali
ty [
mm
mra
d]
Welding
Laserline GmbH, Germany 4
Diode Laser Diode Laser TypesTypes forfor Metal Metal WeldingWelding
Fiber-coupled diode laser
OEM Module LDM
Direct diode laser, LDL 240, LDL 160, LDL 80 and LDL 40
Laserline GmbH, Germany 5
Diode Laser Diode Laser withwith assistassist Gas Gas NozzleNozzle
Welding with diode laser on robot
Coaxial assist gas nozzle
Photo: IWB, Munich
Laserline GmbH, Germany 6
Optics with different beam dimensions and working distances
Beam switch for fiber-coupled diode laser
Shield gas nozzle, cross jet
Integrated welding sensor
CCD camera, cover slide cassette for
welding optics
Cover slide monitor
Mechanical shutter, stack management
Interfaces: Profibus-DP, Interbus,
Ethernet, PC-based control
WeldingWelding: : OptionsOptions
Laserline GmbH, Germany 7
WeldingWelding of Metals: Joints of Metals: Joints
Butt joint
Lap joint
Parallel joint
T - joint
Cross joint
Corner joint
Angle joint
Multiple joint
Schweißtechnik, VDI Verlag, 1996
Laserline GmbH, Germany 8
WeldingWelding of Metals: of Metals: WeldWeld SeamSeam GeometryGeometry
I - weld on
butt joint
V - weld Y - weld
Fillet - welds
Area - weld Spot - weldsDouble -
fillet - weld Schweißtechnik, VDI Verlag, 1996
Laserline GmbH, Germany 9
Laser Welding & Conventional WeldingLaser Welding & Conventional Welding
12
10
8
6
4
2
Laser HPDL Plasma MIG/MAG TIG(CO2, YAG)
Welding speed for different materials
Parameters
Butt joint: 1 mm
Laser: 2,5 kW
Conventional welding
Suitable parameters
Austenitic steel
Construction steel
Aluminum
Source: HIGHYAG
Laserline GmbH, Germany 10
Joint TolerancesJoint Tolerances
Laser HPDL Plasma MIG/MAG TIG(CO2, YAG)
1,25
1,00
0,75
0,50
0,25
0,00
Perm
issib
le t
ole
ran
ce
in
mm
Position tolerance of weld source
Gap tolerance
Source: HIGHYAG
Laserline GmbH, Germany 11
Comparison of Comparison of EnergyEnergy Density Density
0 101 102 103 104 105 106 107 108 109 [W/cm2]
Intensity
Welding Method
New application
for diode lasers
Gas Fusion Cutting
MIG/TIG Welding
Plasma Welding
Laser-/Electron Beam Welding
Diode Laser
Resistance Welding
Arc Welding
Laserline GmbH, Germany 12
0
1000
2000
3000
4000
5000
6000
7000
0 1 2 3 4 5 6
Penetration [mm]
Sp
ee
d [
mm
/min
]
LPSS Spot = 0.3 mm
LDF Spot = 0.4 mm
ComparisonComparison LDF 400-850 LDF 400-850 withwith Nd:YAG Nd:YAG
LDF 400 - 850
1,8
mm
1,2 mm
0,70 mm
LPSS, 500 W
LPSS, 1000 W
Laserline GmbH, Germany 13
Key Hole Key Hole WeldingWelding withwith Diode Laser Diode Laser
Fiber-coupled diode laser
LDF 1000-2000
Spot size: ! 0.8 mm
Working distance: 70 mm
Speed: 2 m/min
Material: 1.4301
1 m
m
Laserline GmbH, Germany 14
Key Hole Key Hole WeldingWelding withwith Diode Laser Diode Laser
Fiber-coupled diode laser
LDF 1000-4000
Spot size: ! 1.0 mm
Working distance: 85 mm
Speed: 0.5 m/min
Material: 1.4301
6.4
mm
Laserline GmbH, Germany 15
WeldingWelding withwith LDF 1000-4000 LDF 1000-4000
0,0
1,0
2,0
3,0
4,0
5,0
6,0
7,0
0,0 1,0 2,0 3,0 4,0 5,0 6,0 7,0 8,0
weld speed [m/min]
pen
etr
ati
on
dep
th [
mm
]
3500 W
2800 W
2000 W
800 W
power at
workpiece
Laserline GmbH, Germany 16
Workpiece preparation
Workpiece fixing
Welding
Further treatment*)
Weld seam quality
(TIG, MIG, MAG)
*) Grinding, polishing,
handling, production time
Workpiece preparation
Workpiece fixing
Welding
Weld seam quality
Diode laser
Conventional
Welding
Holistic evaluation necessary!
" Reproducibility
" Process stability
" Welding speed
" System downtime
(maintenance, random
failure, planned downtime)
" Gap tolerances
" Possibility of automation
" Product flexibility
Evaluation Method Evaluation Method
Laserline GmbH, Germany 17
Diode Laser
Conventional
WeldingProduction Steps
(TIG
, M
IG, M
AG
)
CostCost Comparison Comparison
Workpiece preparation
Workpiece fixing
Welding
Further treatment
Weld seam quality
medium
medium
high
no
good
medium
medium
low
high
medium
Laserline GmbH, Germany 18
Laser Welding of Metal HousingsLaser Welding of Metal Housings
Overall costs reduced by 70 %
compared to conventional welding
Relative Process Time
Process Conventional Diode laser
Welding 37 % 10 %
Grinding &
Polishing 30 % 9 %
Straightening 33 % 9 %
Total 100% 27 %
Laserline GmbH, Germany 19
Laser Laser WeldingWelding of Metal of Metal HousingsHousings
2 kW fiber-coupled Diode Laser
Higher weld speed
Reduced treatment after welding
Overall costs reduced significantly
compared to conventional welding
Photo: Addmetal, NL
Laserline GmbH, Germany 20
Overlap WeldingOverlap Welding
Overlap welding of car body metal sheets
(not zinc-coated) with diode laser
LDF 1000-2000
Optical power: 1800 W
Spot size: Ø 0,8 mm
Speed: 2,7 m/min.
0,7 mm
0,7 mm
Laserline GmbH, Germany 21
Diode Laser Metal Diode Laser Metal WeldingWelding
Twin diode laser
2 x 700 W
Welding of instrument housings
Substitution of pulsed Nd:YAG
Diode Laser with Cross Jet
and CCD-Camera
Photo: RJ Lasertechnik
Laserline GmbH, Germany 22
Laser Laser WeldingWelding of of StainlessStainless Steel Steel
Reduced production time
1 kW Diode Laser
Homogenous welding result
No further treatment required
Large tolerances in gaps
Laserline GmbH, Germany 23
Laser Laser WeldingWelding of of StainlessStainless Steel Steel
Photo: IREPA
Direct diode laser and robot:
welding of kitchen sinks
Stainless steel welding samples
Laserline GmbH, Germany 24
WeldingWelding of of KitchenKitchen SinksSinks
Direct diode laser on robot
Very smooth surface
No finishing process needed
Laser power: 1 – 4 kW
Welding speed up to 5 m/min
Laserline GmbH, Germany 25
Photo: Addmetal, NL
Step-Seam Welding of ProfilesStep-Seam Welding of Profiles
Fiber-coupled diode laseron robot
Very smooth surface
High-quality welds
No distortion of parts
Laserline GmbH, Germany 26
0,3 mm stainless steel
200 Watt Diode Laser
Weld speed: 1,5 m/min.
Advantages:
Small heat affected zone
High process speed
Even weld surface
Gas proof weld
WeldingWelding of of BatteryBattery HousingHousing
weld seam
Laserline GmbH, Germany 27
0,5 mm stainless steel
Tolerance in heigth: 1 mm
800 Watt diode laser
Weld speed: 2 m/min.
Advantages:
Even weld seam
No Adaptation of heigth
High reproducibility
High process speed
Laser Laser WeldingWelding of of StainlessStainless Steel Steel
Laserline GmbH, Germany 28
Substitution of Substitution of PulsedPulsed Nd:YAG Nd:YAG
Welding of transformer plates
Multi diode laser system with 3
diode laser heads, each 500 W
Results:
Better weld seam
Shorter cycle time
Reduced production costs
Laserline GmbH, Germany 29
Direct diode laser, LDL 80-1000
1000 W
Multi-shift operation in production
Multi-diode laser system
WeldingWelding of of TransformerTransformer PlatesPlates
Laserline GmbH, Germany 30
WeldingWelding of of SawSaw Blades Blades
Direct Diode Laser LDL 80-1000
Optical power: 400 Watt
Material thickness: 1,5 mm
Weld
Laserline GmbH, Germany 31
WeldingWelding withwith Diode Laser: Diode Laser: ExamplesExamples
Micro welding and fine welding
butt joint welding
Laserline GmbH, Germany 32
WeldingWelding withwith Diode Laser: Diode Laser: ExamplesExamples
2 mm deep weld
fine welding
Laserline GmbH, Germany 33
WeldingWelding withwith Diode Laser Diode Laser
stainless steel welding
Welding with diode laser on robot: Erlas
Laserline GmbH, Germany 34
WeldingWelding of of stainless steel tubesstainless steel tubes
Fiber-coupled diode laser
LDF 600-1000
Optical power: 1000 W
Spot : ! 0.6 mm
Welding speed: up to 7.5 m/min
Laserline GmbH, Germany 35
WeldingWelding of of flat heating tubesflat heating tubes
Fiber-coupled diode laser
LDF 1000-2000
Optical power: 2000 W
Spot : ! 1 mm
Welding speed: up to 2.5 m/min
Laserline GmbH, Germany 36
WeldingWelding of of bellows bellows II
Fiber-coupled diode laser
LDF 600-1000
Optical power: 1000 W
Spot : ! 0.6 mm
Welding speed: up to 5 m/min
Laserline GmbH, Germany 37
WeldingWelding of of bellows bellows IIII
Three shift production
Different diametres are possible
Each length is possible
Laserline GmbH, Germany 38
WeldingWelding of of pressure sensorspressure sensors
Fiber-coupled or direct diode laser
Even weld seam
No Adaptation of heigth
High reproducability
High process speed
Stable welding process
Laserline GmbH, Germany 39
Influence of Process GasesInfluence of Process Gases
MünchenTU
Prof. Reinhart
Shield gas: Ar (100 %) Ar CO2 (80 %, 20
%)
Optical power: 3000 W
Welding speed: 0,5 m/min
Material: St 37
Thickness: 3 mm
Laserline GmbH, Germany 40
StepStep WeldingWelding of Zn-coated of Zn-coated PlatesPlates
Fiber-coupled diode laser
LDF 1000-2000
Optical power: 1800 W
Speed: 2.5 m/min
Thickness: 2 x 0.8 mm
Bottom
Top
Laserline GmbH, Germany 41
Substitution of Substitution of cwcw Nd:YAG Laser Nd:YAG Laser
Welding of electromechanical
components
500 W, 600 !m fiber
Material X5 CrNi 18 - 9
Welding speed: 18,9 mm/s
Depth of weld: 0,6 mm
Result:
Comparable welding results
with lower production costs
Laserline GmbH, Germany 42
Hybrid Hybrid WeldingWelding: Nd:YAG & Diode Laser: Nd:YAG & Diode Laser
System set-up:
wavelength coupling
MünchenTU
Prof. Reinhart
Spot geometry
1
2
0,6
Laserline GmbH, Germany 43
Hybrid Hybrid WeldingWelding: Nd:YAG & Diode Laser: Nd:YAG & Diode Laser
Tailored Blanks
Material: AlMg3
Thickness: 1.5 / 1.2 mm
PNd:YAG = 3 kW, pHPDL = 3 kW
Speed = 8 m/min
Fillet Weld
Material: AlMgSi1
Thickness: 2 mm
PNd:YAG = 3 kW, pHPDL = 3 kW
Speed = 5 m/min
MünchenTU
Prof. Reinhart
Laserline GmbH, Germany 44
1 m/min
2 m/min
4 m/min
3 kW
Nd:YAG
3 kW Nd:YAG
and
3 kW diode laser
Hybrid Hybrid WeldingWelding, Cross , Cross Section Section
5 mm5 mm
MünchenTU
Prof. Reinhart
Laserline GmbH, Germany 45
Hybrid Hybrid WeldingWelding of of StainlessStainless Steel Steel
Weld seam surface:
Border seam AlMg3
Weld seam surface:
overlapping sheets AlMg3
MünchenTU
Prof. Reinhart
Laserline GmbH, Germany 46
Performance of Welding ProcessesPerformance of Welding Processes
Welding of thin aluminum alloy sheets at high speed
DC pulsed MIG X ! X
Laser beam X " "
DC MIG and laser hybrid ! ! !
AC pulsed MIG " X !
Thickness: less than 2 mm
Weld speed: over 2 m/min
Joint
gap
Proper
heat input
Beam
stability
Laser AC pulsed MIG hybrid " " "
" good
! not good enough
X bad
Source: DAIHEN
