Can Laser Cutters Cut Metal?

I. Introduction

In the modern diversified and sophisticated manufacturing industry, laser cutting technology plays an indispensable role in various industries due to its distinctive advantages and widespread adaptability.

Whether for complicated structure manufacturing in the aerospace industry creative graphics cutting in the advertising decoration industry, spare parts precision processing in automobile manufacturing, or even manufacturing of micro parts for the electronics industry, laser cutting machines can achieve effective utilization and art creation of materials with high accuracy, high speed, and flexible design.

However, there is a core problem of laser-cutting machines arousing people’s attention despite its widespread application: can laser-cutting machines cut metal? The answer is yes; this characteristic is the key factor to stand out in many industries.

Laser cutting technology can not only handle a variety of metal materials, including stainless steel, carbon steel, aluminum, and copper but also can avoid mechanical stress on the workpiece while keeping extremely high cutting precision because of non-contact fabrication characteristics, thus greatly improving quality and lifespan.

At the same time, laser cutting technology plays an increasingly important role in the metal processing industry due to its fast speed, small heat influence area, and smooth and flat cutting-edge characteristics.

Our passage will further delve into how laser cutting technology cuts different kinds of metals with high efficiency and high accuracy, this technology’s advantages, and its future trends in metal fabrication.

II. Understanding Laser Cutting Technology

Definition and brief history of laser cutting

The laser cutting technique is a technique that utilizes a high energy density laser beam to locally irradiate material, making the irradiated area quickly melt, vaporize, or reach the ignition point, achieving precise cutting technology.

This technology dates back to the late 1960s and was initially used in the scientific research fields.

With the development of laser technology and cost decreasing, laser cutting is gradually used in industrial production, and widely applied in sheet metal fabrication, automobile manufacturing, aerospace, precision machinery, and other industries.

Types of lasers used in cutting metals

There are three main laser types in metal cutting:

CO₂ lasers: CO₂ laser is the most common and widest-used laser cutting equipment in the market. It uses a CO₂ gas mixture as a working substance and generates constant and pulse laser beams. It features high power, good laser beam quality, and fast cutting speed, which is suitable for most metals and nonmetal material cutting.

Fiber lasers: fiber lasers have been developed quickly and widely used in a few years owing to their tight structure, high efficiency, and low maintenance cost. Its working principle is to use fiber doped with rare earth elements as the gain medium, and the laser wavelength generated is much shorter, which is more suitable for metal material cutting. The cutting effect is particularly good on highly reflective metal materials such as stainless steel, carbon steel, and aluminum.

YAG solid lasers: YAG solid lasers are appreciated in specific areas because of their high stability and durability. It adopts crystal as a laser medium and generates lasers that can produce near-infrared wavelengths, suitable for thin sheet metal and nonmetal material cutting. Although its power is lower than CO₂ laser and fiber laser, it still stands out in some refined and high-precision metal cutting applications.

III. The Mechanics of Laser Cutting Metal

First of all, it is paramount to understand the laser cutting basic working principle. The core component of a laser cutting machine is a laser generator, which can produce a highly concentrated monochromatic beam, that is laser.

This laser features extremely high power density and can be focused by the optical system into an extremely fine spot with a diameter of only tens to hundreds of microns, making the energy per unit area highly concentrated.

When such a high-intensity laser beam hits a metal surface, there are two kinds of main physical effects will be generated: absorption and reflection.

As for specific wavelength laser, metal material will absorb parts of laser power, and these parts of energy will quickly be transformed into thermal energy, making the temperature of a local area of metal rise sharply in a short period, reaching the melting point or even the boiling point.

At the same time, the remaining unabsorbed laser energy may be reflected or scattered.

Once the parts of the metal material are up to a molten or vaporized state, the laser cutting head will move at a preset speed, and guide the laser beam along a designed path, thus realizing the precise cutting towards the metal material.

Because the laser beam energy is highly concentrated and the transfer speed is fast, most of the heat generated during the cutting process is merely restricted to a small area, ensuring the surrounding material will not be affected by heat, and ensuring the quality and precision of the cutting edge.

Besides, when cutting thick metal sheets, it is usually assisted by injection of high-pressure gas (such as oxygen, nitrogen, etc.)

On the one hand, these gases can blow away the slag produced during the cutting process and keep the cutting mouth clean.

On the other hand, the O2 can serve as a combustion accelerator to accelerate metal oxidation reactions, further increasing cutting speed and efficiency.

IV. Laser Cutters and Metals

Types of Metals Suitable for Laser Cutting

Laser cutting technology can be used to cut various types of metal materials, including carbon steel, silicon steel, stainless steel, aluminum alloy, and titanium alloy.

These materials have different requirements for laser-cutting machines. For example, CO₂ laser cutting machine can cut carbon steel within 20 mm, stainless steel within 10 mm, and aluminum alloy within 8 mm.

This proves that it is very pivotal to choose proper laser cutting machines to achieve high-quality metal cutting.

Factors Influencing Metal Cutting with Lasers

Metal thickness: metal sheet thickness is the key factor in determining the efficiency and quality of the laser cutting. Thinner metal material is easier to penetrate and cut quickly by laser, and the increasing thickness may need higher laser power and slower cutting speed to ensure the quality of the cuts.

Laser power needs: different metal materials and thicknesses have different requirements for laser power. The higher laser power can quickly melt the workpiece and effectively blow away the molten material with auxiliary gas. Choosing the proper laser power is not only related to cutting efficiency but also directly affects the machining costs and workpiece quality.

The Role of Laser Type in Metal Cutting

CO₂ laser is suitable for cutting nonmetal and metal materials within a certain range because of its long wavelength characteristics. And CO₂ laser cutting machine shows good adaptability for medium and thick plate carbon steel and stainless steel.

However, with the advancement of fiber laser technology, especially for metal cutting application optimization, the advantages of fiber laser cutting machines are becoming increasingly prominent.

Because the short wave long light beam generated by fiber lasers is easier to absorb by metal, it can exhibit higher electro-optical conversion efficiency, lower operation cost and more stable cutting properties when cutting metals like stainless steel, carbon steel, and aluminum alloy.

Besides, fiber lasers feature tight structures, and simple maintenance, which makes them the mainstream equipment in the modern metal cutting sphere.

In all, to choose which kind of laser cutting machine, metal types, and thickness should be considered, a comprehensive evaluation will be made according to actual production needs, economic benefits, and future technological development trends.

Thickness limitations: How thick can laser cutters go?

CO₂ laser cutting machine:

As for mild steel, CO₂ laser cutting machines of industrial level can handle thicker plates ranging from 0.5 mm to 25 mm, and the high-power equipment can be up to 30 mm.

As for stainless steel and aluminum, due to the different efficiency of laser energy absorbing, the thickness that can be cut is smaller than that of mild steel under the same power, about 0.5mm to 20mm.

Fiber laser cutting machine:

Fiber laser cutting machines feature prominent advantages when cutting thin sheet metals like stainless steel, carbon steel, and aluminum alloys owing to their higher electro-optical conversion efficiency and more concentrated beam quality.

As for thin metal sheets (like 0.5 mm to 40 mm), the fiber laser cutting machine showcases excellent cutting effects and precision.

With the power improvement, parts of high-end fiber laser cutting machines can cut metal sheets up to 80 mm to 100 mm.

However, in actual application, the specific cutting thickness is related to many factors like processing speed, precision requirement, cut quality, and economy.

Besides, as for very thick metal material, multi-pass or composite processes are often required for cutting.

V. Advantages of Using Laser Cutters for Metals

Precision and accuracy

The core advantages of laser cutting technology lie in its extraordinary accuracy and precision. The laser beams can be focused into tiny spots, and move precisely along a preset path, achieving micron-level fine cutting.

This high precision ensures the consistency of parts size and strict control of tolerances, especially suitable for producing precise components and complicated patterns.

What’s more, due to the non-contact processing of laser cutting, it avoids deformation and stress caused by traditional mechanical cutting, further improving the quality of the workpiece.

Processing speed

Compared with traditional metal cutting methods (like stamping, plasma cutting, or waterjet cutting), the speed of laser cutting is apparently improving.

Laser cutting is constant and fast, with no need to replace tools and adjust equipment, greatly shortening the production cycle period.

Especially in mass-scale production and assembly line operations, laser cutting machines can work stably and constantly at a high-speed rate, significantly improving production efficiency.

Diversity and adaptability of material and shape

Laser cutting machines feature a good material application range, which can efficiently cut various metal materials including mild steel, stainless steel, aluminum, copper, and even alloys and special metals.

At the same time, laser cutting is not limited to the complexity of patterns, whether for simple straight cutting, or complex curved outline, even the two-dimensional or three-dimensional parts, it can finish easily.

This gives designers more freedom and creative space in product design, promoting the manufacturing to move to a higher level of personalized and custom development.

VI. Considerations When Cutting Metal with Lasers

Material property considerations: reflectivity and thermal conductivity

Reflectivity: different kinds of metal have different absorbing abilities to the laser beam. For example, high-reflectivity metal materials such as aluminum, and copper, are irradiated by laser, and part of the energy will be reflected instead of being absorbed and converted into heat, which may affect the speed and effect of the melt or vaporized metal. Therefore, when dealing with this sort of metal, a laser with a higher power rate or special assistant gas and optical system will be required to strengthen the laser absorb rate.

Thermal conductivity: the metal's thermal conductivity rate determines how quickly heat is transferred when it is heated. The heat of high thermal conductivity metal like aluminum will quickly spread to the surrounding area, reducing the energy density of the laser focus point. This may need to adjust the laser parameters to keep sufficient localized heat accumulation for effective cutting.

On the contrary, for metals with low thermal conductivity, such as stainless steel, it is easier to achieve high-efficiency cutting because heat is less likely to diffuse.

Laser power and cutting speed influence

Laser power: laser power directly affects the cutting speed and depth. The higher power will melt the workpiece faster and cut the workpiece more smoothly. However, a higher power may lead to workpieces being over-melted or deformed. Thus, choosing the proper laser power is more important.

Cutting speed: cutting speed interacts with laser power, and mutually determines the final cutting quality and effects. Improving the cutting speed properly can reduce heat input, and heat-affected zone, thus acquiring better cutting edge quality. However, moving too fast may result in incomplete cuts or failure to penetrate the material. Finding the best match between the power rate and cutting speed can achieve an optimized cutting effect, and ensure productivity efficiency.

VII. Conclusion

Recall our passage, whether for precise cutting with different types of metals (such as mild steel, stainless steel, and aluminum), or precise control towards metal thickness, reflectivity, and thermal conductivity, laser cutting technology has shown its extraordinary properties.

Meanwhile, with the continuous advancement of laser power, and the development of advanced technology like fiber laser cutting, the ability to deal with thicker or hard-to-cut metal material has been continuously strengthened.

From simple two-dimensional cutting to complex three-dimensional shaping, from mass-scale criteria production to personalized custom design, laser cutting technology will push the whole metal fabrication into advancement, further strengthening its role in modern efficiency and precise technology.

ADH Machine Tool, a leading manufacturer and exporter of laser cutting, press brake, and shearing machines, will offer you endless possibilities. Welcome to browse our official website or contact our salesman.