What are the differences between welding using a laser and welding using TIG or MIG/MAG? How do you know when you should use laser hardening and when to use induction hardening? There are several considerations when deciding whether to use lasers in industrial manufacturing and the processing of products. In part four of laser school, we’ll explain more about the different laser methods and how they differ from manufacturing methods that do not involve laser

Laser welding versus TIG-MIG/MAG welding

Laser welding is a quick and precise welding method where the high-energy concentrated laser beam provides very localised heating. This means the heat has a minimal impact on the material surrounding the weld, which reduces the risk of deformations that could require post-processing. Another strength of laser welding is that double-sided access is not required as it allows for single-sided access.
The most common alternatives to laser welding are TIG-MIG/MAG, spot welding, and bonding/additives. TIG-MIG/MAG welding has a huge heat impact on the material, which increases the risk of deformation and the need for post-processing. It also requires a lot of energy and can have inconsistent results. Often you need to grind the weld after using TIG-MIG/MAG, which can be avoided when using laser welding. Spot welding requires double-sided access and takes longer than laser welding. Bonding using additives is a time-consuming process as it involves curing. The additives themselves are often environmentally hazardous.

Laser hardening versus case hardening

Laser hardening involves heating metal using a highly concentrated laser beam. The heated area is then quickly cooled by the cold surrounding base material, which changes the structure of the metal, making it stronger and more durable. Selective hardening is possible thanks to the concentrated laser beam, which reinforces very well-defined surfaces of the product.

The most common alternatives to laser hardening are induction hardening and case hardening. Induction hardening can be used to harden large and small surfaces. Depending on the geometries of the products, you need to adapt the hardening to the product in question. Case hardening allows you to harden large volumes of material at the same time, but since hardening takes place in a furnace, the entire product must be hardened instead of selected areas.

Laser soldering versus manual soldering

Laser soldering involves joining two metal objects by melting an additive using a laser beam. The result is a dense joint with minimal dilution of the base material. It provides a dense coating with little or no porosity and a well-finished surface, and it improves the material’s natural resistance to corrosion, wear, and oxidization.

The alternatives to laser soldering are manual soldering or plasma soldering. Manual soldering has a low investment cost but is environmentally hazardous and often has varying results. Plasma soldering was once used in the automotive industry but has since seen considerable competition from laser soldering due to the latter being more efficient and giving a better-looking result.

Laser cutting versus water cutting

When cutting with a laser, the laser beam heats the material to the point of evaporation so that the beam can penetrate the material and create a cut. Laser cutting is a common method of cutting nowadays and one that is often standardised, providing neat cuts with a consistently high quality.

Other cutting methods include plasma cutting, water cutting, and gas cutting. Although heating and cutting using plasma is suited to thick materials, it does not result in a neat cut and is a relatively uncommon cutting method nowadays. Water cutting differs from other methods as it is a cold process. Although it is environmentally friendly, it is not as quick as laser cutting when cutting thin materials. Although gas cutting is a simple and mobile method, it can lead to inconsistent results and a poor work environment.

Additive manufacturing using lasers versus arc additive manufacturing

Additive manufacturing, or 3D printing, using a laser is quick and gives good results. Heating the material using a laser beam while melting an additive such as a wire or powder can allow a product to be coated, repaired, or given a new shape. Stable robot movements and the precision of the laser head ensure a consistent level of energy, which keeps the need for post-processing to a minimum. Lasers are one of several useful methods for use in additive manufacturing. Another method is arc additive manufacturing, but this generates a lot of heat and has poorer tolerances.

If you want to know more about the benefits of lasers versus traditional technologies, visit our website, and please contact me if you have any questions. In “Laser School: Part 5”, we will talk about laser stations and how they are built. You don’t want to miss that!