Materials guide
Laser engraving of glass and ceramics: preparing for a validated result
A logo on a bottle, a design on a tile and an identifier on a technical ceramic do not affect the material in the same way. The choice of process depends on the composition, surface condition and intended use of the part. Non-contact engraving guarantees neither the absence of cracks nor the retention of the part’s properties.
Engraving, marking and cutting: three distinct objectives
Distinguish engraving that changes the relief from marking that mainly seeks legible contrast. On glass, a frosted appearance may be accompanied by surface microcracks and chips resulting from a thermal mechanism. This does not demonstrate a reproducible depth on all glass.
Cutting separates the part through its thickness. The ability to engrave does not demonstrate the ability to cut. For glass or ceramics, validate the material, thickness, process and edge quality separately. This guide does not constitute machine validation for this operation.
Glass: heating can cause fractures
Local heating of glass can induce thermal stresses and cause cracks or breakage. Sensitivity depends in particular on the properties of the glass, its geometry and its surface condition. To prepare your project with NWS LASER, specify the part number and treatments. Do not extrapolate a result from one glass to another, especially if the composition or heat treatment differs.
For a mirror, specify whether the project concerns the glass or its reflective coating. The technology must match the layer actually being processed; these operations must be qualified separately. The label “glass-compatible” is therefore not enough to define the operation.
Ceramics: consider composition and surface
Glazed porcelain is not equivalent to technical ceramic. The laser response depends in particular on the material and the absorption of radiation at the wavelength used. The process must be qualified for the material reference and surface concerned, with no universal selection rule or assumed machine compatibility.
Specify whether the pattern is intended to modify the glaze, a coating or the ceramic body. Define the end use: decoration, identification or functional component. Legibility alone does not demonstrate that the characteristics of a technical part remain acceptable.
Identify the material before any testing
Gather the supplier part number, known composition, thickness and treatments of the part. Report any paints, glazes, metallization, adhesives and auxiliary products. Request the technical documents and safety data sheets available for these products. A coating FDS does not replace identification of the substrate; an unknown material must not be declared compatible based on resemblance alone.
Validate a representative sample
Prepare parts with the same part number, geometry and surface condition as the intended production batch. Define acceptance criteria before testing: contrast, legibility, appearance, acceptable relief, and inspection for cracks or chips. Document the result and the configuration used in accordance with the manufacturer's instructions.
A visually successful pattern alone does not demonstrate the integrity of glass or the suitability of a part for its intended use. For a demanding application, have the product manager define any additional inspections. There is no universal recipe here for power, speed, focusing or number of passes.
Plan for extraction and prevention in the workshop
Microparticles and sometimes gases may be emitted when working with glass. Assess emissions from the substrate and its coatings, then provide extraction and filtration suited to the substances and process. General ventilation alone must not be considered validation that exposure is controlled.
Lasers present risks to the eyes and skin, as well as associated chemical risks; some also present a fire hazard. Prioritize beam containment and comply with the integrated safeguards and the instructions. Auxiliary products and residues must also be included in the fire-risk assessment. Any personal protective equipment should be selected after assessment, not based on a universal recommendation.
Pour préparer votre échange avec NWS Laser, transmettez la référence matière, le motif et les critères attendus par le formulaire de contact, à info@nwslaser.fr ou au +33 4 81 68 04 04.
Frequently asked questions
- Can crack-free glass engraving be guaranteed?
- No. Composition, internal stresses and the process affect the risk. Representative tests and appropriate inspections are necessary; good visual appearance does not guarantee integrity.
- Is a UV laser always preferable to CO₂?
- No. The choice depends on the material, the absorption of radiation and the surface to be treated. Provide NWS LASER with your material reference and the desired result to prepare for process qualification, without presuming machine compatibility or generalizing to all glass and ceramics.
- Can an engraving machine also cut these materials?
- This cannot be inferred from its ability to engrave. Cutting requires a separate assessment and process validation on the part concerned.
Sources and documentation
NWS LASER
Your context, before the solution.
Specify the material, model or need, operating constraints and available documentation. The NWS Laser team will help you identify the next useful step.