Is there a difference between plasma and laser cutting? While both use high-temperatures to cut through materials, they are quite different. With that being said, let’s take a closer look at each method and how they differ.
An Overview Of Plasma Cutting Method
Plasma Cutting, what is it?
Plasma cutting is a process that entails the use of a jet of hot ionized gas to cut through materials. This jet of ionized gas is known as a plasma. The temperature of this plasma can reach an incredible 40,000 degrees Fahrenheit.
In plasma, cutting a combination of compressed gases and inert gases such as hydrogen and nitrogen are passed through a nozzle at high speed. The gases combined with high speeds and a concentrated area of pressure result in an electrically conductive gas formation. This is the gas that is referred to as plasma.
Plasma Cutting uses
Plasma cutting is a process primarily used to cut metals. In particular, it is preferred for cutting electrically charged metals such as aluminum. It is also used to cut thick sheets of metal. Overall, it can be used to cut metals such as steel, stainless steel, and of course, aluminum.
Advantages of plasma cutting over laser cutting
- Compared to laser cutting, plasma cutters can cut thicker sheets of metal
- Industrial plasma cutting is cheaper compared to laser cutting
- Plasma cutters can cut all types of metals, including electrically conductive metals
- Is quicker at cutting medium thick sheets of metal than laser cutting
- Maintenance cost of plasma equipment is lower compared to laser equipment
Disadvantages of plasma cutting
- Unlike laser cutting can only be used to cut metals
- When it comes to cutting precision, laser cutters offer a higher level of precision than plasma cutters
An Overview Of Laser Cutting Method
Laser cutting: What is it?
Laser cutting entails the use of amplified laser light. The cutting process is typically performed using a computer. In this case, a computer numerical control or CNC, which guarantees a high precision rate.
With the help of optics, the laser light is focused onto a small point. And as it enters the optics, it becomes smaller and hotter. Aided by the computer, the focused laser beam is able to cut through materials.
Laser cutting uses
Laser cutting is used to cut all kinds of materials from metals to ceramics. Due to its high precision and accuracy, it is mainly used in fabrication works. Also, this type of cutting is employed in engraving works.
Advantages of laser cutting over Plasma cutting
- Laser cutting uses less energy compared to plasma cutting
- Laser cutters offer a higher precision rate compared to plasma cutters
- Unlike plasma cutters, laser cutters can cut a wide variety of materials, including metals, plastics, and ceramics
- Laser cutting cannot damage the workpiece, unlike plasma cutting
Disadvantages of laser cutting over Plasma cutting
- Laser cutting equipment is pricier compared to plasma cutting equipment
- Laser cutters cannot cut thicker sheets of metal
Comparisons between plasma and laser cutting
As already noted, there are many differences to note in the plasma cutting vs laser cutting comparison. Here are the main differences between the two.
Initial setup cost
Both cutting processes require the acquisition of certain equipment. When compared, the equipment and the plasma cutting machine are cheaper. As such, when it comes to purchasing cost, the laser has a higher purchase cost.
When comparing the two, plasma cutting is the more economical of the two. The initial cost is significantly lower than the initial cost of setting up a laser cutter.
When it comes to operating costs, plasma is again the cheaper of the two. When you take into account things such as power, abrasive, and consumables, plasma is cheaper. On average, you will spend $15 per hour for plasma cutting. For laser cutting, the cost goes up to $20 per hour.
The speed at which you can cut materials is important. When compared, plasma has a higher production rate. This means you can cut more materials with one plasma cutter than you would with one laser cutter.
To put things into perspective, a plasma cutter can cut anywhere between 60 to 200 inches per minute. This is quite impressive when compared to the 20 to 70 inches per minute that you get from a laser cutter.
In terms of the overall quality of the cut, we are talking about the squareness of the finished edges. When comparing the two, laser cutting is the undisputed better option. Laser cutting produces nice square cuts. However, on thicker steel, it can generate pierce spatter and some dross.
By comparison, it is almost guaranteed that you are going to get pierce spatter from plasma cutting. This can be blamed on the large kerf width you get with plasma cutting.
Cut part precision
The resulting cut size compared to the programmed cut size is what we call cut part precision. This is often affected by heat distortion and kerf width. Laser cutting yields an impressive +/-0.005″ of the cut part with a 0.025″. Kerf width.
On thicker sheets of steel, though, lasers can cause heat distortions. Plasma cutting, on the other hand, produces a cut part of +/-0.020″. As for the kerf width, it stands at an average of 0.150 inches. Plasma cutting also results in some heat distortions.
When it comes to flexibility, we consider what kind of materials you can cut with each process. As mentioned earlier, plasma cutting is ideal for electrically charged metals. As such, this process can only be used to cut metals.
On the other hand, laser cutting can be used on metals, plastics, fiberglass, and even ceramics. Thus you have more flexibility with laser cutting. With plasma cutting, you are limited to metals.
Which is the better of the two And For What?
When compared side by side, both cutting processes have their place in the industrial world. While laser cutting can cut a wider variety of materials, it struggles when cutting thicker sheets of metal.
Laser cutters can only cut mild steel sheets of not more than 25mm in thickness. Plasma cutters, on the other hand, can cut metals of up to 150 mm in thickness. As such, the question of which process is better boiled down to your needs.
If you have thicker sheets of metal to cut, go for plasma; however, if you want precision cutting of thinner sheets of metal or any other material, go for laser.
Overall, both cutting processes are useful. They both have their pros and cons, and it is hard to choose one over the other. Also, they are different in their usage and what they can be used on. Thus, it all comes down to the application.