Fiber Laser Equipment: Metal vs. Plastic Marking

There are major differences in the way fiber lasers are used for marking metals and plastics.From the perspectives of material characteristics, equipment parameters, and applicable situations, it helps users understand how to choose the most suitable solution.This article examines the practical effectiveness, cost efficiency, and common problems with using fiber laser marking machines in the processing of metals and plastics, providing practical references for industrial marking.

Why is there such a difference between marking metals and plastics?

Many people think that laser marking machines are "all-purpose tools," but in actual use they find that the results for metals and plastics are totally different.For example, when etching a QR code onto stainless steel, the result is clear and the code is resistant to wear, but when you change to a plastic case, if you're not careful you can burn the edges.The differences are mainly related to the absorptive and heat-resistant properties of the materials.

The characteristics of the material determine the marking effect.

The ability of metals to absorb light.

Metals in general have a high absorption rate of fiber laser light, and especially so for common industrial metals like iron and aluminum.With 20 watts of power, it can create a stable oxide layer on the surface of metal, and the text or pattern has high contrast.But remember--highly reflective materials like stainless steel need to have the focal point adjusted, or else the energy will be insufficient.

The "temperature trap" in plastic marking.

Plastic absorbs less energy from the 1064nm beam, so the main effect is carbonization of the surface.Too much power will burn right through the PET film, while too little will leave no trace.Recently, one of our customers was trying to mark ABS plastic with a logo, and only after repeated testing did we discover that the "sweet spot" was 30 % power with high-frequency pulses.

How should the parameters be set?

A golden combination.

For most applications, the recommended settings for marking metals are 70-100 % power, 20-50 kHz frequency, and 800-1200 mm / s speed.For example, the Q-switched mode can be used to make a clear mark 0.1 mm deep, which will last for 10 years.

Three steps to successful plastic marking.

1. Start with low power (10-30 %).

2. Gradually raise frequency to 80-120kHz to reduce heat effect.

3. Use compressed air to blow out the molten slag.

Last week I helped a company that makes PCs adjust the serial numbers on the casing. We finally achieved the desired effect with 25W power and 100kHz frequency.

Which scenes are more suitable for fiber lasers?

This is the area where laser marking really shines.

Permanent identification of tools and measuring instruments.

• Medical device tracking codes.

• Aviation and aerospace parts.

In particular, fiber laser marking is much more reliable than inkjet printing for applications that require resistance to corrosion and wear.

The hidden advantages of plastic marking.

Although not as widely used as metals, they are very popular in these areas.

• Electrical insulation marking (does not conduct electricity).

• Food packaging date stamping (without chemical pollution).

• Backlighted keys (two-stage processing, with the label on the back and the display on the front).

How do you calculate the cost?

Although metal marking machines require a higher initial investment (around US $ 10,000 to US $ 20,000), they have the advantage of lower maintenance costs and less material usage.Plastic marking may seem cheap, but in actuality it requires frequent changes to the equipment and adjustments to parameters, which in turn increases labor costs.If the monthly production exceeds 50,000 units, they suggest that it is more worthwhile to directly use an automated platform.

Finally, we remind everyone: Don't be fooled by "one-size-fits-all" solutions. A truly professional manufacturer will offer customized solutions based on the materials.If you're not sure, send a sample to the manufacturer and let them test it.