Laser Marking of Nickel Alloys

The course covers the optimization of key parameters such as laser power, scanning speed, and frequency, helping users to solve problems such as unclear markings and material damage.Applicable to engineers, operators and laser equipment users.

Why is it so difficult to laser mark nickel-based alloys?

Nickel alloys are widely used in aerospace and precision manufacturing because of their ability to withstand high temperatures and corrosion. But their high reflectivity and hardness make them a "technical challenge" for laser marking.If the parameters are not adjusted properly, the marks will be blurred or the surface of the material will be damaged.Don't panic. We'll now take a look at how to deal with these parameters!

Three steps to key parameters.

The first step is to "get to know the temper of the material.

Nickel-based alloys such as Inconel 718 and Hastelloy have different compositions, so it is imperative to confirm the material before marking it.For example, alloys with a high chromium content have a low absorption rate for lasers, so you might need to adjust the power. On the other hand, you have to reduce energy when working with thin-walled pieces, to avoid burning through.

Step Two: The seesaw of power and speed.

If the power is too high, the drill gets burnt out; if it's too low, it can't drill deep enough.It is recommended to start with a low power output (for example, 20-30W) and a medium scan speed (500-800mm / s).If the markings are blurred, you should increase the speed rather than blindly increasing the power, which can reduce the heat-affected zone and keep the material properties intact.

Step 3: "Invisible assistance" from frequency and density.

If the frequency is too low, it will break the connection.For fine print, the frequency is set at 60-80 kHz and the spacing at 0.05 mm. For large areas of graphics, the frequency is lowered (20-40 kHz) and the spacing is increased to 0.1 mm.Remember: Choose a 45 ° or 90 ° angle for filling, to avoid the appearance of uneven texture caused by the overlapping of light spots.

A guide to avoiding pitfalls.

What can you do about yellowing?

It's probably oxidizing too much. Try nitrogen protection, or lower the peak power by 10 % and change the number of laser pulses from one to two.

Can you tolerate the sharp edges?

Check whether the focusing lens is dirty, and keep the diameter of the light spot to between 0.02 and 0.05 mm.Another trick is to add a 0.5-mm stroke to the outer edge of the image to eliminate the "fringe.

Is it true that deep carving is not uniform in depth?

It's possible that the speed of the mirror is uneven.You can also manually set parameters to divide the work into zones, for example slowing down by 10 % in thick areas while keeping the original speed in thin areas. This is more precise than a global adjustment.

Don't be lazy about equipment maintenance.

At least once a month, the laser head lens should be cleaned, and the temperature sensor should be calibrated.In particular, in the humid summer months, remember to add drying agents to the optical system.No matter how well the parameters are adjusted, if the equipment is not in proper working order, it will be useless.