Cutting operations are an essential aspect of part production in the manufacturing sector. One of the most important machining techniques is laser cutting of sheet metal. It is suitable for cutting metal, alloy and non-metal parts.
Sheet metal laser cutting is a thermal cutting process in which beams of light (lasers) are directed at the workpiece to melt or vaporize materials until the desired shape is achieved. This technique is one of the most effective for cutting metal sheets.
This article will provide important information about laser cutting of sheet metal before using it. Let's get started right away.
What is sheet metal laser cutting?
Subtractive manufacturing processes are critical for modifying materials to produce parts. Sheet metal laser cutting is one of the standard methods for cutting and removing components from a workpiece. This technique involves cutting pieces of material using laser beams.
Laser cutting technology is based on computer numerical control (CNC) technology, which guarantees its impeccable precision. Before the CNC or laser cutting process, the operator must enter codes or programs with detailed designs or patterns into the computer.
The sheet metal laser cutting process
Laser metal cutting uses laser beams to melt metals and alloys, creating smooth, sharp cuts. The laser cutting process consists of two synchronous operations.
First, the material absorbs the focused laser beam – the energy that causes the cut. Secondly, the cutting nozzle, which is arranged concentrically to the lasers, supplies the process gas required for cutting. The gas protects the machining head from vapors and spatter and helps remove excess gas from the cutting gap.
There are basically three methods for laser cutting sheet metal.
1. Laser beam fusion cutting
Laser fusion cutting uses a shielding gas, usually nitrogen. The low-reaction process gas continuously evaporates the material in the cutting gap. When the molten material is removed, the shielding gas prevents oxidation on the cutting edge without affecting the process.
This laser cutting process is suitable for cutting flat and thin sheets of aluminum alloys and stainless steel where a high level of aesthetics and fewer post-processing operations are required.
2. Laser sublimation cutting
As the name suggests, laser sublimation cutting vaporizes the material. Instead of melting the material as with other laser cutting processes, it is immediately transferred from the solid state to the gaseous state – sublimation.
Like fusion cutting, laser sublimation cutting uses inert gases to expel vapor from the cut material. This means that there are no oxidizing agents on the cutting edge. It is widely used to cut organic materials such as wood, leather, textiles, etc.
3. Laser beam flame cutting
Laser flame cutting uses a flammable gas – oxygen – to force out molten material. The laser heats the part and creates spontaneous combustion after melting the material. Oxygen gas provides more energy for the cutting process through oxidation – an exothermic reaction.
Flame cutting is ideal for cutting carbon steel and fusible materials such as ceramics. This cutting process can cause burns to the cutting surface because the gas is an oxidizing agent. Proper optimization of process parameters helps prevent burr formation.
Types of laser for sheet metal cutting
Manufacturers typically use three different types of lasers to cut materials. Each type of laser has different characteristics and is more suitable for cutting certain materials. Below is an overview of the three types of lasers for cutting.
1. Fiber laser
Fiber laser cutting machines use fiberglass to cut. They generate very high power for powerful and precise cuts. This laser is part of a family of solid-state lasers that consists of a “seed laser” that is amplified by special glass fibers.
These lasers are suitable for cutting almost all materials, from metals to alloys and non-metals such as wood, glass and plastics. In addition to cutting, they are also ideal for other operations such as annealing and engraving.
Additionally, they are the longest-lasting lasers, with an extended lifespan of more than 25,000 hours and requiring less maintenance.
2.CO 2 Laser
With 2 Lasers produce laser beams by passing an electrical current through a tube filled with a mixture of noble gases, mainly nitrogen and helium. They are the most common forms of laser because they are efficient, cheap and cut many types of materials at high speeds.
However, they produce less cutting power compared to fiber lasers. Therefore, they are not a good choice for laser cutting of sheet metal. Typically, manufacturers prefer to use them to cut non-metals and organic materials such as wood, paper, acrylic, etc.
3. Crystal laser (Nd:YAG or Nd:YVO)
Crystal lasers produce their beams from Nd:YAG crystals (neodymium-doped yttrium aluminum garnet) or Nd:YVO crystals (neodymium-doped yttrium orthovanadate, YVO4). However, the latter are more common.
These crystals produce beams with high cutting performance. However, they are expensive and do not last long, as they have a low half-life of around 8,000 to 15,000 hours. They are widely used to cut plastics, metals and non-metals, including ceramics.
7 Advantages of Sheet Metal Laser Cutting
Let's explore the benefits of sheet metal laser cutting for the manufacturing sector.
1. High precision and accuracy
Laser cutting is suitable for cutting metal sheets due to its extreme precision. The machines are equipped with the ability to perform complex cuts with extreme precision and accuracy. In industry, laser cutting is the preferred technique for cutting sheet metal with specific details that require tight tolerances.
Some cutters can make precise cuts with an accuracy of up to 0.0005 inches. For this reason, it is an important application in most manufacturing companies. Because lasers melt metal parts, cutters produce little to no burrs. Instead, they leave a clean, smooth, and crisp edge.
2. Automated process
Laser cutting is done using CNC (Computer Numerical Control) systems. Once the technical operator inserts the programs into the computer, the process runs independently. Therefore, less human intervention and labor are required. Additionally, with increased cutting efficiency, there is little or no room for error.
3. Damage prevention
There is a misconception that laser cutting of metal causes deformation. However, this is wrong. The heat from laser cutting only affects small parts of the material and does not affect tolerance.
Furthermore, the laser cutting process is fast; lasers heat and melt the parts to be removed. Therefore, heat has no significant effect on other parts of the material. In most cases, there will be no warping or warping of your material.
4. Compatible with most materials
Another important advantage of this subtractive manufacturing method is the ability to work with a wide variety of materials. Easily cuts any material, be it copper, aluminum, stainless steel or even titanium. Finally, lasers are used at very high temperatures to melt the material.
5. Relatively low cost
Laser cutting machines are expensive. However, compared to other CNC machines, they are more economical. What's more, it's a one-size-fits-all machine – meaning a single laser cutting machine is ideal for all your cutting needs. You do not need to make modifications to the machine for different cutting operations.
Plus, it's durable. The device has no contact with the materials being cut, so there is little or no friction or surface wear. Additionally, it does not consist of multiple parts, so less maintenance and services are required. In general, the operating costs of a laser cutter are lower compared to other traditional manufacturing tools.
6. High versatility
In addition to laser cutting's compatibility with most materials, the process is extremely versatile. Unlike other devices, you can use a laser cutter for multiple cutting functions, from simple to complex cuts and those that require tight tolerances and complex designs. This feature makes it an excellent choice for most industries.
7. Low power consumption
In fact, laser cutters require electricity to effectively heat and melt materials during cutting. However, cutting technology is more energy efficient than other cutting methods.
Plus, unlike other machines, it has fewer moving parts, which means lower energy needs. Furthermore, the machine's high speed allows for fast cutting, saving time and energy.
The Disadvantages of Laser Cutting Sheet Metal
The main disadvantages of laser cutting sheet metal include:
1. Requires technical operator
To use a laser cutting machine effectively, you need an expert who understands all of its functions and can quickly identify problems to make appropriate corrections in a timely manner. If you do not set the device correctly, you may damage its materials or the machine itself. Therefore, if you want to perform a laser cutting service, you need to hire a professional.
2. Limitations on metal thickness
Laser cutters are highly compatible with most materials, especially sheet metal. However, when working with thick metals, other cutting techniques must be considered. In most manufacturing industries, laser cutters cut aluminum sheets with a maximum thickness of 15 mm and steel sheets with a thickness of 6 mm.
3. Release of harmful fumes and gases
We discovered that laser cutting uses heat to melt the cut materials. As the materials melt, the machine releases harmful fumes and gases into the environment. Therefore, it is recommended to use these machines in well-ventilated environments.
4. High initial investment
The costs of purchasing a high-quality laser cutter are high. They cost more than $2,000, almost double the price of other cutting machines such as: B. waterjet cutter. To run a laser cutting business, you must be willing to make an initial investment.
Important Tips for Laser Cutting Parts
To meet the laser cutting accuracy and quality requirements of your parts, follow the guidelines below.
1. Choose the right materials
Material selection is critical to any manufacturing process. The material you choose for your part depends on the properties you want in the final product. In addition to metal sheets such as aluminum and zinc, plastics and other polymers are good options for manufacturing parts depending on your needs. Some properties that manufacturers look for when choosing a material are flexibility, formability, ductility, rigidity, etc.
2. Design with software that creates vector files
Laser cutting machines only work with vector files. Therefore, use software like Adobe Illustrator to vectorize your designs. These files have formats like .ai, .step, .eps, etc.
3. Think about the cut
The cut is the part of the material that vaporizes when the laser beam hits the part. When designing your piece, you need to consider the cut.
4. Details should not be smaller than the thickness of the metal
Metal thickness is an essential factor to consider when laser cutting. The thicker the metal sheets, the less likely the lasers are to penetrate.
5. Minimum distance between cutting lines
To obtain optimal results in laser cutting, sufficient distance is crucial. The minimum distance for laser sheet metal cutting must match the thickness of your material. For example, if you are cutting a sheet that is 2 mm thick, you must leave a gap of 2 mm.
Laser Cutting Parts Applications
Below are the applications of laser cutting.
1. Medical equipment
Trolleys, beds, surgical instruments, orthopedic nails, rods, etc. They are all made from laser cut metals. Although many surgical instruments are now manufactured using 3D printing, laser cutting is the preferred technique for their manufacture.
2. Jewelry Making
Most jewelry designs contain complex patterns that can be easily recreated with laser cutters. Jewelry is usually made from fine materials. Therefore, laser cutting is suitable for jewelry making.
3. Interior design
Laser cut sheets are great for room dividers, which can improve the overall look of a room and create more space. By combining the precision of laser cutting with the creativity of the manufacturer, you can give your space the custom look you want.
4. Aerospace industry
Due to high dimensional accuracy, the aerospace industry is one of the most important users of laser cutting technology. Most aircraft parts and other equipment such as metal detectors, carts, conveyors, etc. undergo some cutting operations during manufacturing.
Concluding
Finally, you must have a comprehensive knowledge of sheet metal laser cutting. It is an advanced manufacturing process for producing large series and parts with high demands on dimensional accuracy. You can decide whether you want to apply the method to your manufacturing needs.
If you want to work with a company that guarantees high-quality laser cutting services, WaKen's sheet metal cutting service is ideal for your manufacturing needs. We are an ISO certified company offering world-class sheet metal fabrication services for rapid fabrication and custom production. No matter sheet metal bending, stamping, welding, etc., we can meet all your machining needs.
Common questions
Can laser cutters damage my materials?
No. Many people believe that the high temperatures during laser cutting can damage materials. However, laser cutters are precise and work at incredible speeds, so the beam only melts the parts you want to cut. Additionally, the high speed means your materials are not exposed to high temperatures for long.
Should I outsource or purchase my sheet metal parts using a laser cutting machine?
Laser cutting techniques are essential for many manufacturing operations. It is an extremely effective process, suitable for cutting most materials, especially sheet metal.
If you run a small manufacturing service, it is best to outsource your cutting operation. In other words, hire a service provider for your laser cutting needs. This allows you to save costs that can be invested in other aspects of production. Contact Waken for your laser cutting and sheet metal fabrication needs.
What processes can I choose for my project besides laser cutting?
Laser cutting is not the only high-precision cutting method for industrial manufacturing. Should you decide not to use laser cutters for your fabrication or are you not sure how to cut shapes from your sheet metal? Below are excellent alternatives to choose from for your manufacturing needs.
- EDM – Electrical Discharge Machining
- Water jet cutting
- CNC Milling
- Punch
