Laser Marking on Curved Ceramic Surfaces: A Case Study in Equipment Modification

To address the problems of blurriness and breakage in laser etching on curved surfaces, the company offers three low-cost, high-efficiency solutions: upgrading the laser head positioning system, customizing rotating fixtures, and optimizing parameters.

Why is it always so difficult to mark curved ceramic surfaces?

Let's first talk about some of the headaches involved in actual production.Last week I was visited by a manufacturer of ceramic watch bezels for smartwatches. They were complaining that using a traditional laser machine to etch the logo on the curved surface of the bezel either made the lines blurry or caused cracks to form.In fact, this is a very typical problem. The fixed focal length design of ordinary flat surface marking machines is like trying to use a ruler to measure a watermelon--it just doesn't work.

Three steps to a successful transformation.

The "universal joint" for the laser head.

The most critical change was in the laser head positioning system.We added a six-axis linkage module to our existing equipment, and combined it with infrared distance sensors, so that the laser beam could follow the contours of a curved surface like the claws of a gecko.Test data shows that after modification, the focal length deviation was reduced from ± 1.5 mm to ± 0.2 mm.

The fixture must be "tailor-made.

Don't underestimate the importance of this rotary device; we designed a vacuum suction + silicone buffer composite fixture for ceramic parts.In particular, when dealing with curved surfaces, using a 3D scanner to create a customized fixture for the ceramic piece is like putting it in a snug-fitting vest so that it doesn ’ t move around during the marking process.

The more parameters, the better?

Laser surgery is all about "gentle cutting.After 200 tests, we found that the best results were obtained with a pulse width of 8ns and a frequency of 35kHz.Here's a reminder for everyone: Don't blindly trust the "ceramics" setting on your equipment. The actual parameters depend on the material batch and the curvature of the surface.

The results of the renovation.

After being reorganized, a certain Guangdong bathroom fixtures factory saw its good products rate jump from 63 % to 92 %, and its hourly production capacity increase by 40 pieces.What surprised me most was that the company was able to recoup the cost of the retooling in half a year with the money it saved on rework.So the key to equipment improvement is to find the pain points and fix them, because sometimes a small investment can make a big difference.

Tips for everyday maintenance.

And finally, two words on maintenance: The modified spindle needs lubricant every week, and the laser head should be equipped with a positive pressure dust removal device.During the rainy season, remember to keep the humidity below 40 % so that condensation doesn't form on the surface of the ceramics, which would affect the quality of the engraving.