In basic terms, laser marking is a process that uses a beam of concentrated light to create a precise and permanent mark on a range of surfaces, including materials like steel, titanium, copper, ceramic, glass, plastic, and wood.
Laser marking machines can create marks like serial numbers, barcodes, and graphics. When choosing a laser marking machine, there are several things you should consider.
Here are three key considerations you need to know about.
Consideration #1: Is a UV or fiber laser marking machine better for your requirements?
The two main types of laser marking machines are UV laser machines and fiber laser machines. Both look similar and both can engrave numerous materials. But a UV laser marking machine can engrave more materials than a fiber laser machine. However, a UV machine has less power for carving and engraving over metal materials.
Although the two types of machines look similar on the outside, the technology they use is different. They use different power suppliers and the UV laser must be refrigerated by a water chiller while the fiber laser is refrigerated by air.
The UV laser technology also allows for greater multifunctionality and capacity for marking over different materials, including non-metals, and it uses an automatization system such as linear guide engraving and rotary engraving.
Although a UV laser marking system has many advantages over a fiber laser machine process and is the most widely-used form of laser marking, fiber laser marking does have many benefits, including its ability to carve at high speed on a wide variety of metal surfaces.
Consideration #2: Which materials do you want to mark?
Seeing as a UV laser marking machine can mark more materials, it is often the preferred choice. But your choice of machine will largely be dependent on the exact materials you need to engrave. Here are the key materials you can use with each machine.
Common UV laser applications
UV lasers can mark:
· Some metals
· Some stones
· All plastics
· All glass
· All papers
· All leathers
· All woods
· All ceramics
Common fiber laser applications
Fiber lasers can mark:
· All metals
· Some plastics
· Some stones
· Some leathers
· Some paper
Consideration #3: Know the difference between marking, engraving, and etching
Although terms like laser marking, engraving, and etching are often used interchangeably by lay people, there are differences between the three methods. Before you opt for a laser marking machine, it is important you know the difference between the three marking processes, to ensure you purchase the right machine for your needs.
The laser marking process
Laser marking is achieved by slowly moving a low-powered beam across a surface using a method known as discoloration. The laser heats the material to cause oxidation under the surface of the material, turning it black. Low temperatures are then used to anneal the surface. The process creates high-contrast marks without causing any disruption to the material.
The laser engraving process
The laser engraving process involves the laser beam removing the surface of the material to expose a cavity which then reveals an image. During the engraving process, the laser generates high heat, which causes the material to vaporize, leaving a cavity in the surface. Laser engraving is a quick process, although to create deeper marks, the process needs to be repeated several times.
The laser etching process
Laser etching is a subset of laser engraving. The process involves the beam’s heat melting the surface of a material. When the melted material expands, it causes a raised mark. Laser etching can be performed on bare, anodized, or plated metal surfaces, as well as ceramics and polymers.