Why Can’t CO2 Laser Marking Machine Be Used for Metal?

| Working principle of CO2 laser marking machine

CO2 laser marking machine is a device that uses CO2 gas laser as a light source to mark, engrave or cut the surface of the workpiece through a laser beam. Its working principle mainly includes laser generation, beam transmission, focusing and control system.

Laser generation: The CO2 laser marking machine contains a CO2 gas laser. When the gas is electrified and excited, the molecular energy level of the gas transitions, and then a laser beam with a wavelength of 10.6um is generated.

Beam transmission: The laser beam is released from the laser, and after adjustment by the reflector and lens system, the quality and intensity of the laser beam are guaranteed, and then the laser beam is transmitted to the surface of the workpiece.

Laser focusing: The lens system focuses the laser beam to a very small focus, generating a light spot with high energy density, which has a thermal effect with the material on the surface of the workpiece, causing the material on the surface of the workpiece to evaporate or change color.

Control system: The output power of the laser, the movement trajectory and frequency of the laser beam and other parameters are controlled by a computer control system to achieve marking and engraving of different shapes.

CO2 laser marking machine uses CO2 gas laser to generate laser beam, focuses the laser beam onto the surface of the workpiece through the lens system for marking or engraving, and realizes precise processing operation through the control system. This equipment is widely used in the field of non-metallic material marking, with the advantages of high efficiency, precision and environmental protection.

| Characteristics of CO2 laser marking machine

CO2 laser marking machine has the following characteristics:

1. High precision: CO2 laser marking machine can achieve very fine marking and engraving, with excellent precision and resolution.

2. High speed: The laser marking speed is fast, and a large number of workpieces can be processed in a short time, improving production efficiency.

3. High clarity: The marking result of CO2 laser marking machine is clear and high in clarity, and it can achieve the marking of complex graphics and details.

4. Easy to operate: It is easy to operate, and the marking content can be flexibly adjusted through the computer control system, which is easy to learn and use.

5. Long-lasting marking: The marking effect of CO2 laser marking is long-lasting and durable, not easy to wear or fade, and is suitable for long-term retention of marking and identification needs.

6. Non-contact processing: Laser marking does not require contact with the surface of the workpiece, which reduces damage to the workpiece and is suitable for materials with high surface requirements.

7. Environmental protection and energy saving: The laser marking process does not require the use of chemical fluorescence, so no post-processing is required, no chemical pollution and waste are generated, and it meets environmental protection requirements.

CO2 laser marking machine has the characteristics of high precision, high speed, high clarity, easy operation, durability, non-contact processing, environmental protection and energy saving, so it is widely used in industrial production and manufacturing fields.

| Application fields of CO2 laser marking machine

CO2 laser marking machines are widely used in many fields, mainly including but not limited to the following aspects:

Industrial manufacturing

CO2 laser marking machines are widely used in industrial manufacturing to identify and track the production batch information of products and parts, anti-counterfeiting marks, etc., and are widely used in automobiles, electronics, machinery, aerospace and other fields.

Packaging industry

CO2 laser marking machines can mark packaging materials in the packaging industry, such as cartons, paper boxes, plastic bags and other products for tracking, tracing and anti-counterfeiting.

Pharmaceutical industry

Using CO2 laser marking technology on pharmaceutical packaging can help regulators and consumers trace the source of products and ensure the authenticity and safety of products.

Food industry

Using CO2 laser marking machines on food packaging is often used to mark information such as production date, batch number, barcode, etc., to facilitate tracing the source of food and ensure food safety.

Leather processing

CO2 laser marking machines are widely used in the production of leather products, and can be used for personalized customized marking, engraving patterns, cutting and shaping, etc., to enhance the added value of products.

Woodworking industry

In the field of wood processing, CO2 laser marking machines can perform wood marking, engraving, cutting and other processes, and are used in furniture manufacturing, handicraft engraving and other aspects.

In general, CO2 laser marking machines are widely used in various fields of industrial production and manufacturing, with the advantages of high efficiency, precision and environmental protection, providing reliable solutions for product identification, decoration, processing, etc.

Metal materials have some unique characteristics during laser processing, including thermal conductivity, absorptivity and reaction to laser:

1. Thermal conductivity and absorptivity of metal materials:

Metal materials usually have high thermal conductivity and can quickly transfer heat to the surrounding of the material, resulting in an increase in temperature around the heated area during laser processing.

Metal materials have different absorptivity for lasers of different wavelengths. Generally speaking, metal materials have a low absorptivity for common CO2 lasers (wavelength of 10.6um), and most of the energy will be reflected or transmitted, resulting in low processing efficiency.

2. Reaction and influence of metal materials on lasers:

● Reflection and transmission: The reflectivity of the metal surface for CO2 lasers is relatively high, and most of the laser energy will be reflected, and only a small part can be absorbed. Transmission generally does not occur, and the laser energy is directly reflected or absorbed.

● Absorption: Metal materials will absorb part of the energy under the action of high-energy-density lasers, resulting in a rapid increase in the temperature of the local area. When the temperature of the metal surface exceeds the melting point of the material, melting or evaporation will occur.

● Evaporation and ablation: During the laser engraving or cutting process, metal materials will evaporate and ablate, evaporating or gasifying the metal materials, thereby processing the surface of the material.

Metal materials have the characteristics of high thermal conductivity and low absorption rate during laser processing, resulting in low laser processing efficiency. However, by controlling laser parameters, using appropriate auxiliary gases and adjusting the processing process, processing operations such as cutting, engraving and marking of metal materials can still be achieved. In addition, the reaction of metal materials to lasers will be affected by factors such as metal type, surface treatment status, and laser parameters, and the processing process needs to be carefully controlled and adjusted according to actual conditions.

The main reasons why CO2 laser marking machines can’t be used for metal materials are as follows:

1. Unsuitable wavelength

The wavelength of CO2 laser is 10.6 microns, and metal materials are not sensitive to this wavelength. Metal materials are usually more absorbing to shorter wavelength lasers. For example, the wavelength of fiber laser is about 1.06 microns, which is more suitable for metal material processing.

2. Low absorption rate

Metal materials have a low absorption rate for CO2 lasers, and most of the laser energy cannot be effectively absorbed and converted into heat energy. This makes it impossible to effectively process metal materials and produce clear marks or scratches.

3. High reflectivity

Metal materials have a high reflectivity. When CO2 laser irradiates the metal surface, most of the energy will be reflected back. This makes it difficult to fully concentrate the laser energy on the metal surface and achieve accurate marking effects.

4. High material processing requirements

Metal materials usually require lasers with higher energy density for processing, while CO2 laser marking machines have a low energy density and cannot effectively process metals. Metal materials usually require higher power solid lasers or fiber lasers and other equipment for processing.

5. Scope of application

CO2 laser marking machines are suitable for non-metallic materials, such as plastics, ceramics, etc., while metal materials require other types of laser equipment for processing.

In summary, CO2 laser marking machines cannot be used for marking metal materials, mainly due to limitations such as wavelength, absorption rate, and reflectivity. When choosing laser marking equipment, it is necessary to select according to the characteristics and requirements of the material to obtain the best processing effect.

Choosing a laser marking machine that suits you needs to consider many factors, including understanding of needs, budget, material type, process requirements, etc. The following are several key factors to consider when choosing a laser marking machine:

1. Material type

First, you need to determine the type of material you need to mark. Different types of laser marking machines are suitable for different types of materials, such as CO2 lasers are suitable for non-metallic materials, while fiber lasers are suitable for metal materials. Make sure the laser marking machine you choose is suitable for the material you want to process.

2. Process requirements

Consider your specific requirements for product marking, such as marking effect, accuracy, speed, etc. Based on these requirements, choose the appropriate laser marking machine model and configuration to ensure that the desired marking effect can be achieved.

3. Demand and production efficiency

Based on your actual demand and production efficiency, select appropriate laser marking machine workbench size, power size, marking speed and other parameters. For scenarios with high mass production and high efficiency requirements, you can choose a laser marking machine with higher power and faster working speed.

4. Budget

The prices of laser marking machines vary. Choose a suitable laser marking machine based on your budget preset. Consider maintenance costs and operating costs at the same time. When purchasing a laser marking machine, you should not only consider the purchase cost, but also the overall operating cost.

5. Brand reputation and after-sales service

Choose a well-known brand of laser equipment supplier to ensure product quality and after-sales service; when purchasing equipment, pay attention to whether training and technical support are provided to use and maintain the laser marking machine.

6. Your own technical level and usage needs

If you do not have professional knowledge and experience in laser processing, you can consider choosing a laser marking machine that is simple to operate, easy to learn and easy to use. At the same time, choose the appropriate laser marking machine function according to your project needs and marking requirements.

In summary, choosing a laser marking machine that suits you needs to comprehensively consider factors such as material type, process requirements, budget, demand and production efficiency, brand reputation and after-sales service, your own technical level and usage needs. It is recommended that you can further consult Suntop professional laser technicians to recommend a suitable laser marking machine for you according to your needs.