How to use laser cutting on steel, sheet metal and aluminium

Laser technology is widely used to cut steel, aluminium and sheet metal. In general, metalworking is required especially in the production sectors that deal with industrial components, but it is not limited to it. 

To date, this process is able to support the creation and design of various objects thanks to the continuous evolution of technologies and machinery.

Thanks to laser cutting, it is possible to customise metal materials according to the customer's needs, even for complex processes, both for small volumes and for mass production.

How to set the right parameters for the correct execution of laser cutting on metal materials

Before proceeding with the cut, a well-defined technical preparation is necessary. In fact, values such as power, speed, gas pressure and focal point must be set correctly depending on the characteristics of the material on which you want to work.

When managed correctly, these parameters ensure workpiece machining without imperfections such as rough parts or inaccurate cuts.

Let's see together the correct settings to take into account before and during metalworking.

• Laser power: must be calibrated based on the type of metal, thickness and type of processing.
• Cutting speed: together with power it is one of the most important parameters as it is directly interdependent. In fact, the higher the speed, the greater the power must be.
• Focal positioning: it is a question of correctly positioning the laser on the affected area. This depends on the type of cut you want to make and the material itself.
• Gas pressure: the most widely used laser operates via CO2, however other types of gas composition are possible. In the case of oxygen, this parameter is set according to the thickness, in an inversely proportional manner: the more often the material and the lower the pressure and vice versa.

Instead of using gas cutting with nitrogen, it is preferable to work with stainless steel. You will need to ensure that you operate with high precision lenses.

Types of metals suitable for laser cutting

• non-ferrous metals (copper, magnesium, brass, bronze, tin, zinc, aluminium etc.);
• precious metals (gold, silver, platinum);
• titanium;
• stainless steel;
• structural steel.

Each of these metals has its own thermal conductivity, so it is always good to consider whether to use a laser flame (uses oxygen as a cutting gas), a laser fusion cut (often used for aluminium and stainless steel) or a sublimation cut.

Types of laser cutting on steel for industrial production

There are four different laser cutting techniques suitable for metalworking. Let us look at them.

CO2 laser

Suitable for cutting and welding, it is among the first types of lasers and the longest-lasting. 

Nd:YAG laser

Works through infrared and therefore suitable for most metals since they are able to absorb energy without changing. However, the limitations of this technique are primarily in terms of machine management and maintenance, which leads to workflow interruptions and longer production times.

Excimer laser

Often used in the field of electronics because it allows high-precision cuts and micromachining.

fibre laser (latest technology)

Laser that works with fibre optics and rare earths instead of CO2. Often it is silica glass fibre optics to obtain a laser that is easy to control even in the event of dust or vibrations caused by the assembly line during processing. In addition, the low energy consumption, the higher operating speed and the ability to work even on very reflective metals, have made the fibre laser one of the most used in recent years especially for the cutting of aluminium and copper.

Conclusions

Laser is ideal for cutting materials such as steel, aluminium and metal sheets. However, it is important to consider the composition, thickness and other intrinsic characteristics of the piece in order to choose the most suitable technique. 

Carefully evaluate the various options and if you are not sure of the best solution, contact our experts. We have consultants who can help you.