A Case Study: Stainless Steel Nameplates

This article provides a detailed explanation of the process of laser marking stainless steel curved surfaces for car parts, revealing how precise parameter settings and advanced equipment can be used to produce perfect marks. It covers the key points of laser marking technology, the operating procedures, and solutions to common problems.

Why does the car badge have to be perfect?

In the automobile manufacturing industry, part identification is not only an "ID card" for the product, but also relates to the manufacturer's reputation and the safety of the vehicle.This is especially true of stainless steel labels, which are exposed to high temperatures, oil, and vibration. If the labels become blurry, fall off, or even shift position, the lightest consequence is that the customer will complain. The worst case is that the labels become unreadable, which could lead to safety problems.The precision and durability of the engraving thus became the key to the craft.

Three keys to success in laser marking on stainless steel

Don't fall into the trap of buying the wrong equipment.

The ordinary laser machine has difficulty "seeing" curved surfaces, so it is necessary to choose a three-dimensional laser device with a dynamic focusing system.Don't be stingy with the budget, an autofocus machine will save you a lot of trouble in the long run," he says, particularly for parts like car door handles and engine supports, with their complex curves.

Adjusting the parameters is like brewing coffee.

The three parameters of power, frequency and speed had to be "grounded down.For example, if the power is too high when working with a 2-mm thick stainless steel sheet, the surface will be burned and pitted, while if the frequency is too low, the laser will not penetrate.We've tested this, and using a 30-watt fiber laser at 20 kHz and 600 mm / s, the marking is clear and doesn't damage the material. The result is as if you had measured it with a ruler.

Pre-processing is more important than you think.

Don't think that just wiping the surface clean will do the job! The rust-proofing oil on stainless steel must be removed with a special solvent, otherwise the marking process will produce a lot of smoke and will leave a "flowered face" of uneven depth.If you have the means, I suggest an ultrasonic cleaner, which is ten times as reliable as hand scrubbing.

Don't panic when you encounter these problems.

What should be done about the yellowing of the edges of the signs?

Eighty percent of the time it's because the nitrogen purity isn't high enough.I have encountered customers who have used industrial nitrogen, resulting in an oxide layer that can be scraped off.Remember, the money you save on cylinders is the life of your equipment.

How to solve the problem of inconsistent thickness in curved letters?

First check to see if the fixture is tight. If the parts are just a little loose, the entire effect is ruined.There is also a little-known fact: reducing the marking speed by 15 % and reducing the fill spacing by 0.02 mm can effectively improve the "wave pattern" on curved surfaces.

Is it normal for a coin to rust after a mark has been made on it?

In fact, the areas where the stainless steel has been marked actually form an oxidized layer, which makes them even more corrosion-resistant.If rust appears, then the material is checked. Some suppliers will pass off inferior 201 stainless steel as 304, but a drop of chemical will reveal the truth.

The answer is a secret that saves costs and preserves quality.

Don't be superstitious about imported raw materials; domestic high-purity nitrogen gas cylinders are now quite good; use scraps for parameter testing before batch production; it's much cheaper to lubricate the guide rails periodically than to repair them afterwards.The secret to good craftsmanship is not throwing money at a problem, but rather controlling every detail.