TWI Technical Literature Review 23066
By Paola De Bono
'Micro laser welding' of monometallic and bimetallic joints is a very active field of investigation within the scientific community. A comprehensive literature review has been carried out to clarify the work performed to date. Focus has been directed to a range of materials (thin sheets and foils), which are typically being considered for micro laser welding applications; specifically, copper (Cu), aluminium (Al), titanium (Ti), stainless steel (SS) and steel (the latter just for Al to steel dissimilar joining) as monometallic and dissimilar joining. For the purposes of this literature review, the term 'micro laser welding' refers to penetration depths up to 1000?m.
The following information has typically been found from the available literature:
- An understanding of the relationship between the laser welding parameter(s) and the work piece being welded, and/or
- Quality, microstructure and/or properties of the welded joint.
This literature review has focused on published literature on laser welding with fibre and disc continuous wave (CW) laser sources. It does not include studies using CW diode, CO2 lasers or any pulsed lasers, for the reasons below.
Fibre and disc CW laser sources:
- Present greater potential to weld thin sheets and foils with higher productivity than pulsed sources.
- Their beam can be fibre delivered, which makes them more suitable for implementation in a manufacturing environment than CO2 lasers.
- Present higher beam quality than diode lasers.