Laser Engraving FAQs
Laser engraving has become a crucial process for many industries around the world, transforming manufacturing and production lines. But it’s a process that bears many similarities to other types of laser processes, and one would be forgiven for sometimes not knowing what differentiates them!
Do you want to find out more about engraving with lasers? Or perhaps you’re looking for some answers to see which is the right process for you? We have answered some of the most frequently asked engraving questions below.
What is laser engraving?
Laser engraving is the process of leaving a permanent deep mark in a material using a laser beam. Unlike other more traditional methods, the heat of the beam will melt and vaporise the portion of material that it is being aimed at. What’s left behind is a smooth, permanent engraving.
There will be a contrast in colour between the surface layer of the material and the engraving, meaning it’ll be easily visible to the user.
How does it differ to laser marking, etching and ablation?
The process has close links to the marking, etching and ablation processes as they all work with or alter the surface layer of a material. The difference between them comes from how deep they go into the surface of the material being processed and the desired outcome.
Marking aims to leave a mark on the surface layer of the material without removing anything. It instead causes a colour change beneath the surface (read our marking FAQs here).
Etching leaves a small indent in a material, no greater than 0.001”.
Ablation is the process of removing a surface layer from a material, click here to read our ablation FAQs. This may be for cleaning purposes or to prepare a material for other treatment (read our cleaning FAQs here).
Engraving, on the other hand, is used to leave a mark with much deeper depths. For example, here we laser engraved stainless steel to a depth of 1.5mm.
What will happen to my material during the process?
Only the area where you are aiming the laser beam will be affected. It is a non-contact process, instead using the heat and energy of the laser to melt and vaporise the area that is being worked with. This means no other damage will be caused to the surrounding area of the material, including substrate areas.
Can photos and images be engraved into a material using a fiber laser?
Absolutely, yes! High-quality photos and images are regularly engraved into a range of materials through photo laser engraving. Photos/images could for example be engraved into technology items (e.g. mobile phones) as well as jewellery, ID badges, signage, gifts, etc.
Adding photos/images is a very personal touch and is used by some as an added security feature, as the engraving(s) are an identifying mark and can’t (easily) be removed. Photos and images can be engraved onto all the materials mentioned below, but most frequently engrave metals and plastics.
The strength of a image/photo laser engraving is largely dependent on the quality of the source image, we therefore recommend high-resolution photos with a minimum of 600 DPI and higher. See our detailed article on this topic here.
What materials can I use laser engraving on?
Engraving can be used on a huge variety of materials, which includes:
- Metals – a wide range of metals, including:
- Non-reflective metals – such as pewter (a tin alloy), steel, stainless steel and titanium
- Reflective metals such as aluminium, brass, bronze, copper and gold
- Plastics (only with a CO2 laser) and
- Stone – lasers can engrave hard stone surfaces (e.g. marble and granite) for applications such as tombstones and signage
Note: We are asked frequently about the engraving of wood with a fiber laser. This isn’t recommended, technically a fiber laser can engrave, but it leaves a charred and burned engraving. For engraving wood, a CO2 laser should be used.
Engraving tiles is made easy with a laser from SPI. Each material can present its own challenges, hence the need for a reliable and efficient process. For example, brass is a metal with a high level of reflectivity and thermal conductivity, characteristics that could make some setups struggle. This is why using a fiber laser, in particular, is especially beneficial; we have covered more on this below.
Which industries will you find this process in?
Given the fact that the engraving process can work with such a huge variety of materials, it’s unsurprising that it enjoys usage in many industries. These include:
- Aerospace – adding identification tags, bar codes and serial numbers to thousands of parts
- Automotive (including e-mobility) – engraving VIN codes, in parts manufacturing, adding of identification codes, etc.
- Electronics – the engraving of traceability labels and serial numbers in particular
- Jewellery – used in hallmarking, adding personal messages and in jewellery design
- Medical– adding traceability labels and serial numbers once again is important and
- Semi-conductors – the intricate engraving of identification marks and serial numbers
What are some applications for laser engraving?
Generally, laser engraving is used for either aesthetic purposes or for more industrial reasons. Its aesthetic use comes from its ability to leave engravings on a range of items, both large and small. For example, perhaps the most popular use for this is within the jewellery industry.
Its more industrial usage comes from its ability to create high-quality and easily readable bar codes, identification tags, or serial numbers. While laser marking also does this on the surface of an object, such as best before dates on items like milk cartons, sometimes a deeper engraving is needed.
Some examples of specific articles we have written about engraving applications are:
- The removal of thermal barrier coats (TBCs) from super alloys. This helps to extend the service life of components and prevent heat loss
- The engraving of stainless steel. There may be various reasons that this is done, perhaps to engrave manufacturer parts with serial numbers for tracking
- The laser engraving of silver, popular for various pieces of jewellery
- For creating electronic circuity in ceramics
- Engraving is very popular as an application for plaques, trophies and medals
- Engraving can be very successfully used to engrave signage and
- Engraving is frequently used in crafts and gifts (e.g. to engrave a name)
Which laser should I use?
Here at SPI Lasers, we believe that fiber lasers are the most efficient type that one can use for laser engraving. Building on the advantages above, they offer further benefits with a longer service life, a greater level of control and less maintenance times.
Using the latest and most innovative technology, our fiber lasers are also constructed with ‘Fit & Forget’ technology, meaning your products will stay maintenance free.
We recommend using a pulsed fiber laser for the laser engraving process. For that, we have our popular redENERGY® G4 Pulsed Fiber Laser. If you would like to discuss this further, you can find our contact details below.
What are the main benefits of this method over traditional engraving methods?
There are many advantages to using a laser for engraving over other traditional methods. These include:
- Control – The laser user has ultimate control and can engrave to the exact level of depth required, allowing for very fine engraving designs
- Speed – It is a much quicker, more reliable and more efficient process
- High-quality – The engraving that is left will be extremely high-quality, and easily visible to both humans and machines
- Non-contact method – The material being engraved isn’t in contact with the engraving tool as this is a laser beam, this reduces contamination/damage risk, reduces set-up time and increases safety to the user
- Material diversity – A wide-range of materials can be engraved, these include ceramics, glass, various metals, plastics, etc.
- No additional tools – With this process no additional tools are required, which saves on set-up time and a variety of costs
A laser engraving setup can also easily interchanged between various processes. For example, as we examined above, laser engraving is extremely similar to marking or etching, and one setup could be capable of performing each process.
This also means that one setup can be capable of working with multiple materials. This greatly reduces the cost of needing multiple systems.
Have another question?
We hope you have enjoyed our engraving frequently asked questions with answers. We realise that there are so many questions to ask that we can’t cover all of them here! If you have any additional questions, please contact SPI Lasers directly at +44 (0) 1489 779 696. We may also add more questions and answers periodically, so we recommend visiting this page again in the future.
You may find these other frequently asked questions guides useful too –
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