Detailed explanation of the principle, materials, and applications of laser engraving

In the field of modern manufacturing, laser technology is mainly used for various precision components such as reducers, serial numbers of aerospace parts, and so on. Hansheng Automation will delve into this technology and provide a detailed explanation on how to distinguish between laser engraving and laser marking, as well as its relationship with traditional CNC machining.

Laser engraving is a subtractive manufacturing process. It utilizes the high energy density of laser beams to instantly melt, ablate, or vaporize the surface of materials, thereby removing some of the material and leaving grooves or patterns with a certain depth.

In industry terminology, we often distinguish it from laser marking:

Laser engraving: Physical removal of materials, resulting in a noticeable depth of unevenness in the hand feel.

Laser marking: usually only changes the surface color (such as stainless steel annealing blackening), with a relatively smooth surface, commonly used for QR code or serial number marking.

Laser engraving principle: high-energy laser beam

If we use a simple analogy, the principle of laser engraving is like using a magnifying glass to focus sunlight and ignite paper, but it is more controlled and high-energy.

Generate beam: The laser produces a high-intensity beam of light.

Focusing: Focusing a beam of light into an extremely small point (spot) through a lens.

Movement: Under the control of a computer (CNC system), the optical head or galvanometer moves at high speed, and you can imagine it as an invisible paintbrush that "burns" patterns on the material.

CO2 laser engraving machine (10600 nm)

Mainly used in the field of non-metallic materials.
Applicable scenarios: Carving on wood, acrylic (organic glass), leather, fabric, paper and other scenes.
Disadvantage: It is not possible to directly carve exposed metal (unless an auxiliary agent is applied).

Fiber Laser (1064 nm)

Mainly used in the fields of metals and hard plastics.
Applicable scenarios: Used for deep carving or marking of stainless steel, aluminum, brass, and titanium alloys.
Advantages: Extremely fast speed and low maintenance cost.

UV Laser (355 nm)

Mainly used in the fields of ultra-fine machining and heat sensitive materials.
Applicable scenarios: Referred to as "cold processing", suitable for glass, silicon wafers, plastics, and even fruits, with edges that will not be burnt black.

Tip: If you are looking for deep forming of metal parts, simple laser engraving may be less efficient, and combining CNC machining is often a better solution.

Wood: The most common material. Hardwood (such as cherry wood) is suitable for dark carving, while softwood (such as light wood) is easy to cut.

Acrylic: The edges of laser cut acrylic are as smooth as flame polished. Attention: Diode blue light laser cannot process transparent acrylic.

Metal: Anodized aluminum oxide is an excellent canvas for laser engraving, and fiber laser can directly remove the oxide layer to expose the white aluminum substrate.

Leather: The carved effect of genuine leather is highly textured and suitable for making wallets and belts.

Glass: Glass glasses are usually carved using rotating attachments, resulting in a frosted effect.

Attention: Absolutely prohibited materials: PVC (polyvinyl chloride) and synthetic leather. They will release chlorine gas under laser irradiation, which is not only a deadly toxic gas, but also instantly corrodes the metal parts and optical lenses of the machine!

If you need to mark logos, text, or cut thin sheets on the surface of parts, laser is the preferred option.

If you need to manufacture functional metal parts with complex three-dimensional structures, threaded holes, or high precision, CNC machining is irreplaceable.