Laser welding technology is increasingly being utilized in several industrial processes ranging from the production of micro electronics to shipbuilding. However, amongst various applications, the technology has gained considerable acceptance in automotive industries due to its advantages of being cost effective, flexible and faster. The technique has been extensively used for welding automotive parts like bumper, seat rests, tracks, recliners, roof rail, tunnel, motor, gearbox, torque convertors, clutches, side panels, powertrain, exhaust systems and so on.
Benefits of the technique in automotive industry
Laser welding offers many advantages over other joining processes in various automotive manufacturing processes due to its:
- High productivity
- Low distortion rage
- High welding speed and strong welds
- Less distortion on work pieces
- Unmatched advantages in intricate and thin-walled components
- Higher production rates
- Low maintenance
- Low heat input
- Little or no joint preparation; hence saves time and money
- High degree of accuracy due to precision weld beads
- Ability to join dissimilar metals with no filler metal
- Capability to join wide arrays of metals and alloys
These benefits have made this welding technique popular and suitable for many industrial applications that used resistance welding in the past.
Some of the most common types of welding laser types used by automotive industries worldwide are CO2, solid state and fiber lasers. However, advancements in technology have resulted in the invention of high power diode lasers to carry out specific welding applications. Due to improved performance, high power diode welding has received large attention and is slowly replacing traditional laser techniques in many industrial applications.
Laser welding can be broadly classified as conduction and keyhole welding. Both these welding have been extensively used in automotive industry for several complicated joining processes. Let us understand these types in brief.
Conduction welding – In this welding type, heat is transmitted from the surface to the material by thermal conduction. The method provides typically shallow and bowl shaped profile. Conduction welding results in greater process flexibility as it works over a relatively large linear power range. The welding type is best suited for low-power lasers (< 500 W).
Keyhole welding – In this type, laser beam deeply penetrate into the material through a cavity filled with metal vapor. The method is characterized by a high power laser welding. Keyhole welding is best suitable for applications where high aspects ratios are required.
Laser welding technique has achieved industry reputation and wide acceptance and is considered as the most reliable and dependable alternate to TIG welding, EB welding, resistance welding, brazing, silver soldering and adhesive bonding etc.