Lasers – Efficiency and Strength for Lightweighting Laser Processing of Steel

F150 Roof Welding Process

 Laser Joining
 Laser Welding
 Laser Welding with Filler Wire
 Remote Laser Welding
 Laser Brazing
 Laser Hardening
 Laser Softening
 Laser Surface Treatment
 Laser Drilling

Basic Principle
 Laser beam provides a highly concentrated heat source
 Melts metal and even produces vapor (plasma)
 As the laser beam moves along the joint, weld is created upon solidification

 Body in White
 Tubes and Closures
 Powertrain
 Tailor Welded Blanks
 Eliminates bolted assembly for weight
reduction and material cost saving!
 Less assembly steps, remove the need
for machining holes and bolting
assembly!
 Minimal heat input and distortion
 Proven performance and durability

 Weld defects due to
• alloy metallurgical incompatibility
• dissimilar material
• Weld geometry not meeting specifications
Laser Welding with filler wire
• Welded surface not aesthetically smooth
• High power melts the zinc coating
Laser Brazing
• No fast movement between the welds
Laser Remote Welding

Basic Principle
 During laser welding, external wire is fed into the
melt pool
 As the laser beam and wire moves along the joint,
the weld is created upon solidification
 Filler material
 Metal cold/hot wire
Applicability
 Otherwise not laser weldable materials
 Overcome poor weld geometry or fit up
 Change weld chemistry and properties

 Welding of Dissimilar Materials
Steel 4320 – Steel 8620
using Ni-based filler wire
 Laser welding can weld
conventionally un-weldable
materials such as higher carbon
steels and cast irons using filler wire
or pre heat techniques

 Laser Joining
 Laser Welding
 Laser Welding with Filler Wire
 Remote Laser Welding
 Laser Brazing
 Laser Hardening
 Laser Softening
 Laser Surface Treatment
 Laser Drilling

Basic Principle
 Uses a relatively long focusing optic (hence "remote")
 Highly dynamic scanning mirrors enable extremely fast indexing
in-between welds
 Therefore laser is spending more time joining parts and much
less time waiting
Applicability
 Fast and Flexible
 No limitation of weld geometry and speed

Reduction of flange width
 Additional potential for mass reduction
 High beam - to - seam accuracy is required 
 Seam tracking with remote welding head can be utilized

Has been Implemented by:
 BMW (various models inc Liftgate)
 Chrysler Sebring (Liftgate)
 Ford (Mondeo – Roof development)
 GM – Cadillac CTS (Roof and Liftgate)
 Mercedes (Liftgate)
 VW / Audi / SEAT (various)
 Renault (Roof)

 Turn-key integrated laser in-process monitoring
system for laser welding
 High speed camera with illumination
 Robust industrial system can be integrated in
existing laser welding setup
 Defect detection operator feedback (OK/NOK)

Basic Principle
 Laser beam heats the surface just below the melting point
 Very high cooling rate is obtained by moving the beam
 High hardness is achieved

Basic Principle
 Laser beam heats steel sheet above transition
temperature
 By moving the beam, a larger area is treated
and cooling rate is controlled
 Suitable microstructures are formed by
rearrangement and softening is achieved
Applications
 Selective softening for easier formability or
mechanical fastening
 High speed process compared to
conventional heat treatments
 Tailored microstructures

 Laser applications employed by automotive industry for steel
 Welding
 Hardening
 Surface treatment
 Drilling
 The automotive industry has incorporated laser processing in virtually every sub-system of
the automobile
 Ongoing laser innovations will continue to make laser implementation more and more
affordable
 Lasers are a key technology enabler for mass reduction in steel vehicles!