The document discusses Nd:YAG lasers and their use in welding applications. It provides details on the operation of Nd:YAG lasers, including their solid-state design using a rod of yttrium aluminum garnet doped with neodymium. It also discusses their typical power outputs and fiber optic delivery systems. Additionally, it summarizes the capabilities and applications of various laser welding machines that use Nd:YAG lasers, including their power levels, beam diameters, and specialized uses in electronics, medical, automotive, and other industries.

1. SubmittedTo:- Mr. Ankit Bansal Section:- M2E86
Submitted By:-Vardaan Sharma
11101297
A-58

2.  Nd:YAG lasers can operate in both pulsed and continuous mode,
but the other types are limited to pulsed mode.The original and
still popular solid-state design is a single crystal shaped as a rod
approximately 20 mm in diameter and 200 mm long, and the ends
are ground flat.This rod is surrounded by a flash tube containing
xenon or krypton.When flashed, a pulse of light lasting about two
milliseconds is emitted by the laser. Disk shaped crystals are
growing in popularity in the industry, and flash lamps are giving
way to diodes due to their high efficiency.Typical power output for
ruby lasers is 10–20 W, while the Nd:YAG laser outputs between
0.04–6,000W.To deliver the laser beam to the weld area, fibre
optics are usually employed.
 The first type uses one of several solid media, including synthetic
ruby and chromium in aluminum oxide, neodymium in glass
(Nd:glass), and the most common type, crystal composed of
yttrium aluminum garnet doped with neodymium (Nd:YAG).

3. Multifunctional
Laser Welding Machine
Mould Laser Spot
Welding Machine
Galvanometer Scan
Laser Welding Machine

4.  TheW series of pulse Nd:YAG laser welding
systems are suitable for a wide range of
precision spot & seal welding and cutting
applications in the electronics, medical,
automotive and fine mechanics markets.
 Typical applications include:
 Welding of stainless steel, aluminium alloy and
other metals
 Welding of electron guns, titanium capacitors
 Spot welding of optical fibre coupler parts
 Welding of containers
 Seal welding of lithium batteries.

5. Model W-xxx1)
Laser type Flashlamp-pumped pulsed Nd:YAG
laser
Laser wavelength 1064nm
Laser power 50 to 400W depending on model
Laser beam diameter 5-8mm depending on model
Max. laser energy 30-100J depending on model
Pulse width 0.1-10ms, adjustable
Pulse repetition rate 1-200Hz, adjustable
Focused beam diameter <0.2mm
Beam delivery Optical beam delivery with a gas
nozzle
Internal cooling Closed water cooling with chiller
Power requirements 380VAC, 3-phase, 50Hz

6.  The multi-purpose laser welding system is
specially designed for the mould industry and
used in repairing of precision moulds, such as
mould manufacture for digital products,
mobile phone, toy, automobile and
motorcycle, and moulding industry.Through
the repairing of moulds, it is possible to reuse
the moulds, save the production cost and
improve the working efficiency significantly.

7. Model WY180
3-axis stroke of work bench
X=300mm, Y=200mm (X, Y can be
adjusted manually and Z-axis can be
manually motorized to lift maximum
250mm.)
Bearing of work bench ≤200kg
Device weight 300kg
Power supply 220V±10%/50Hz or 380V±10%/50Hz
Laser parameters Laser parameters
Laser type Nd:YAG pulse
Adjusting range of light spot 0.1-0.3mm
Size of light spot 0.2-3.0mm
Laser wavelength 1064nm
Pulse width ≤20ms
Maximum laser power 180W/200W

8.  The working principle of this laser deposition
welding system is to use laser high thermal
energy and the melting technology in spot to
process the welding and repairing of minute
parts. It makes up the shortage of traditional
hydrogen arc welding in repairing precision
surfaces, avoids the two difficulties of
thermal strain and after-treatment, and saves
the production period of mould.

9.  It is specially designed for the mould industry and the
technology is imported from Germany.With unique structure
design, it is suitable for repairing of large, medium and small
moulds.
 Ceramic converging cavity is imported from the Britain. It is
corrosion resistant and high temperature resistant, and has
8-10 years service life.The life of xenon lamp is more than 8
million times.
 Use the most advanced light shielding system to eliminate
the irritation to eyes by light during working.
 The laser head and optics part can be rotated for 360°,
upward/downward lifting and forward/backward pushing,
suitable for repairing of large, medium and small moulds.

10.  This laser welder uses galvanometer scanning
method, features high welding speed, high precision
and good light beam mode, and is suitable for
precision laser spot welding of various parts. During
single spot welding, the working efficiency is 4-10
times higher than common laser spot welding
because the idle stroke positioning time is
significantly reduced.The scanning laser welder
consists ofYAG solid laser, laser power supply, optical
scanning system, 3D adjustable work bench, industrial
PC system, cooling system, laser indication system
and operating cabinet.

11.  This welder is mainly used in highly efficient
laser spot welding or seal welding of mobile
phone shielding case, mobile phone metal
shell, capacitor metal shell, metal shielding
grid in computer, shaver blade, electronic
connector and other electronic products.

12. Model WG100/200
Laser type Nd:YAG
Laser
wavelength
1064nm
Maximum laser
power
100W/200W
Pulse
frequency
≤50Hz
Spot welding
speed
≤15 spots/s
Size of light
spot
0.2-3.0mm
Adjusting
range of light
spot
0.1-0.3mm
Maximum
positioning
speed
≤7000mm/s

13.  Welding of aluminum and its alloys has its specific
features. Aluminum oxidizes strongly above its melting
point.The oxidic layer has a high melting point, and it
does not melt in the welding process.This layer has a
strong ability to absorb gases and vapours, which then get
into the weld metal. Oxidic particle layers may lead to the
presence of oxidic inclusions in the weld metal, which
deteriorates the characteristics of the welded joints.
 When welding aluminum, it is necessary to use a higher
intensity laser beam on the surface of the workpiece, due
to the high reflectivity of aluminum Given the high
reflectivity of the radiation from the surface of aluminum,
it is preferable to use just an Nd:YAG laser.

14.  The high thermal conductivity and the high
coefficient of expansion of aluminium give rise to
major distortions in comparison with steel.The use of
highly concentrated laser beam welding provides the
preconditions for success in addressing these
problems.
 In order to obtain high-quality welded joints, it is
particularly necessary to prepare the surface prior to
laser welding.The oxidic layer along the length of the
surface has to be removed.This surface preparation
minimizes the formation of defects in welding and the
presence of pores and oxidic inclusions in the weld
metal

15. Penetration pass 1.2
Microstructure the heat-affected zone (Al
99.50 %)
Penetration pass 1.5 Microstructure weld metal (Al 99.50 %)

16. Effect of pulse energy on the geometry of
the penetration passes
Dependence of the width and depth of
penetration on the excitation voltage

17.  The weld ability of zinc-coated steel sheets in a lap joint
configuration without a joint clearance by pulsed Nd:YAG
laser beam welding. A mechanism for sufficient
exhaustion of zinc gas for the formation of acceptable
quality welds is proposed.
 The pulsed laser beam welding process is controlled by a
variety of parameters.These include average peak power
density (APPD), mean laser power, traverse speeds and
pulse duration.The present study focuses on the effects of
these main processing parameter on weld quality. Laser
beam welds were produced in 0.7-mm-thick electro
galvanized and 0.7-mm-thick galvanneal steel sheets with
rectangular power pulses.

18. Schematic of zinc gas movement: A — Between
the steel sheets; B — through the keyhole.

19. A —Top view; B — transverse section of
a visually acceptable seam weld produced in
galvanized steel M1 at 2 mm/s using low-
medium APPD (3.73 x 109W/m2, EP = 22.5 J,
TP = 12 ms), and mean power 396 W.

20. A —Top view; B — transverse section
of a visually acceptable seam weld produced
in galvanized steel M1 at 1.5 mm/s using low
medium APPD (3.73 x 109W/m2, EP = 7.5 J,
TP = 4 ms), and mean power 363W.