Application - Laser Welding

Laser welding is a well-established industrial process, but until recently was carried out using continuous wave (CW) or milli second (ms) pulses. Pulsed ns fiber lasers have traditionally been used for marking, engraving and even cutting – all based on ablative processing benefiting from high peak power and short pulse durations. Using these lasers for welding is perhaps counter intuitive but it works! By using high overlap and high frequencies, processing conditions can be achieved that create robust joints in metals.

In fact, the ns welding process can weld just about any metal or combination of metals – including highly reflective and conductive metals. This has always been a challenge due to the formation of brittle intermetallic phases making some metal combinations virtually un-weldable! The ns welding process overcomes these problems through greater control of heat input and through the generation of a very small controlled melt zone.

The ns welding process is a proprietary SPI process and subject to several patents and patent applications.

Laser welding solutions are most frequently used in high volume industries, such as the automotive industry and in manufacturing. The process is extremely popular where the same welding operations are performed repetitively / continuously and can easily and seamlessly be integrated into other processes. This also makes laser welding solutions extremely popular in other industries too, such as in electronics, engineering, medical (the non-contact aspect of the process is important here for sterility), aerospace (including space exploration), jewellery and manufacturing. Welding using lasers can also be used for many other processes such as manufacturing fuel cells, batteries and fine wires for medical devices and other purposes. The use of lasers dramatically reduces the risk of injury to operational staff as they will be quite remote from the area of welding.

The welding of dissimilar metals (i.e. metals, which naturally repeal each other) has always been a challenge traditionally, but this welding challenge has been overcome by the advent of fiber laser welders. Similarly, fiber laser welding has overcome the welding of reflective metals (e.g. copper and aluminium).

Laser welding solutions are most frequently used in high volume industries, such as the automotive industry and in manufacturing. The process is extremely popular where the same welding operations are performed repetitively / continuously and can easily and seamlessly be integrated into other processes. This also makes laser welding  solutions extremely popular in other industries too, such as in electronics, engineering, medical, automotive, jewellery and manufacturing.

There are many benefits associated with welding with lasers. Unlike with traditional welding solutions, lasers guarantee the same accuracy consistently every time, absolutely seamless and cosmetically attractive joints whilst also delivering the ability to weld even the most complicated of requirements. Laser welding is ideally suited to manufacturing processes, where the consistency combined with repeatability guarantee 100% accuracy, which is difficult to emulate with traditional manufacturing techniques. The strength of laser welding joins is much valued, even with welding of dissimilar metals.

The welding process is also popular for the production of micro-precision parts, especially in the medical and electronics industries. The extremely low levels of thermal distortion can’t be emulated traditionally, which is another attraction of laser welding, as is the ability to weld in “difficult to reach” places. In general, there is no need to use flux or filler materials as welding joins can be programmed to work without the need for these, which eliminates the need for post-process cleaning.

For further information about the benefits of fiber laser welding, visit our application insight here.

View the SPI Lasers video – “Laser Spot Welding Copper to Stainless Steel”