RMI Laser Marking Systems are capable of marking on many different types of materials. The most common materials are metals and plastics, but our lasers are also capable of marking on ceramics, composites and semiconductor substrates like silicon.
Materials We Mark
Aluminum is one of the most commonly marked substrates and is used in many industries. Typically, with lighter marking intensity, aluminum will turn white. It looks good when the aluminum is anodized, but white marking is not ideal for bare and cast aluminum. More intense laser settings provide a dark grey or charcoal color.
Each and every RMI Laser series is capable of marking on aluminum and the ideal system for your application depends on your laser marking requirements. Ablation is the most common marking technique for anodized aluminum, but some cases call for etching or engraving. Bare and Cast aluminums are typically annealed (resulting in a white color) unless a specification calls for greater depth and contrast.
Brass and Copper
Brass and copper have high thermal conductivity and thermal transfer properties and are used commonly for wiring, printed circuit boards and pressurized flow meters. Their thermal properties are ideal for laser marking systems for metal because the heat is quickly dissipated. This reduces the impact the laser can have on the structural integrity of the material.
Each and every RMI Laser series is capable of marking on brass and copper and the ideal system for your application depends on your marking requirements. The best marking technique depends on the finish of the brass or copper. Smooth surfaces can offer a soft polished marking affect, but they can also be annealed, etched, or engraved. Granular surface finishes offer little opportunity for polish. Etching or engraving is best in order to provide readability by humans and machines. In some cases a dark anneal can work, but surface irregularities can cause reduced readability.
Tungsten and Carbide are two of the hardest metals on earth and are widely used in tooling and cutting applications. Another popular segment for these substrates is wedding bands for men. Tungsten and carbide are receptive laser marking metals and laser engraving metals.
Each and every RMI Laser series is capable of marking on tungsten and carbide and the ideal system for your application depends on your marking requirements. Because these metals are so hard, etching or engraving is typically not recommended. For carbide, because of the darker color it naturally has, getting a contrasting mark is rather easy with even light laser intensity. A white color is most common when polishing or annealing carbide and the contrast is extremely good. Tungsten, being slightly lighter in color, requires an annealed mark to achieve proper contrast.
Non-semiconductor ceramics come in a variety of shapes and forms. Some are very soft and others are hardened providing a lot of variety. In general, ceramics are a difficult substrate to laser mark as they do not typically absorb a lot of laser light or wavelength.
RMI Laser offers a 532nm Green laser marking system that is better absorbed by certain ceramics. We recommend you have test sampling done to determine the best marking technique to apply to your ceramic material. Ceramics that can be marked are often annealed, but etching and engraving are sometimes possible, too.
Chrome plating provides a stylish and sophisticated finish, and usually requires minimal laser intensity to remove or get through the plating. Care must be taken to ensure the marking happens on the surface only, with no impact to the chrome plating.
Each and every RMI Laser series is capable of marking on chrome plating and the ideal system for your application depends on your marking requirements. We have found that lower powered, faster pulsing lasers yield the best results. Anneal or polish to protect the plating. The annealed marking will be black and the polished marking is typically white.
Coated and Painted Metal
There are many types of coatings used to harden or protect metals from corrosive elements. Some coatings, such as powder coat, are thicker and require more intense laser settings to completely remove. Other coatings, like black oxide, are thin and meant to protect only the surface. These are much easier to ablate and will provide great contrast marking.
Each and every RMI Laser series is capable of marking on coated and painted metals and the ideal system for your application depends on your marking requirements. The UM-1 provides plenty of power to remove or ablate thinner coatings. It may not be ideal for removing a powder coat but it can easily mark a powder coat. Our more powerful fiber lasers come in 20-50 watts, and can easily remove the powder coat and mark the underlying surface. Our fiber lasers can ablate, etch and engrave coated metals.
Fiberglass and Carbon Fiber
Fiber-based materials like fiberglass can be marked with limitations. Because they are composed of individual fibers, the structural integrity can be damaged by the laser, resulting in a blurry marking which cannot be scanned.
Carbon fiber is easier to mark, as the laser typically does not threaten the integrity of the material. However, because of the composition and color of the carbon, the resulting laser mark is always black, which limits contrast and readability.
Each and every RMI Laser series is capable of marking on fiberglass and carbon fiber and the ideal system for your application depends on your marking requirements. Higher wattage lasers can etch or engrave more quickly, but the lower wattage UM-1 laser can perform the same markings with an extended cycle time. The 532nm Green lasers are also a good choice because they are heavily absorbed and don’t cause a lot of melting.
Nickel is commonly used as plating. It can be forged or used as the base metal for some parts, but is usually considered too soft for industrial use. The plating is commonly used for protection of parts from corrosive elements. Care must be taken in order to prevent it from becoming pierced or damaged, which would expose the underlying metallic surface.
Each and every RMI Laser series is capable of marking on nickel and the ideal system for your application depends on your marking requirements. It is our experience that lower powered, faster pulsing lasers yield the best results. Anneal or polish to protect the plating. The annealed marking will be black and the polished marking is typically white. In the rare case that the entire part is comprised of nickel, all marking techniques are appropriate.
Plastics and Polymers
Plastics and polymers are by far the most expansive and variable materials that are marked with lasers. There are so many different chemical compositions that you cannot categorize them easily. Some generalizations can be made in terms of markings and how they will appear, but there is always an exception. We recommend test marking to ensure the best results. A good example of material variability is delrin (AKA Acetal). Black delrin is easy to mark, providing stark white contrast against the black plastic. Black delrin is truly an ideal plastic for showcasing the capabilities of a laser marking system. However, natual delrin is white and does not mark at all with any laser. Even the most powerful laser marking system will not make a mark on this material.
Each and every RMI Laser series is capable of marking on plastics and polymers, the ideal system for your application depends on your marking requirements. Because plastics and some polymers are soft and can burn while marking, Nd: YVO4 or Nd:YAG may be your best bet. These lasers have lightning fast pulse durations resulting in less heat on the material. 532nm Green lasers can be ideal as they have less thermal energy transfer and also are better absorbed by a wider range of plastics.
The most common technique in plastic and polymer marking is color changing. This type of mark uses the energy of the laser beam to alter the molecular structure of the piece, resulting in a change in the color of the substrate without damaging the surface. Some plastics and polymers can be lightly etched or engraved, but consistency is always a concern.
Rubber is an ideal substrate for engraving or etching because it is soft and highly absorbent. However laser marking rubber does not offer contrast. Tires and handles are a few examples of markings done on rubber.
Each and every RMI Laser series is capable of marking on rubber and the ideal system for your application depends on your marking requirements. The only factors to consider are the speed and depth of the marking, as each laser series offers the same exact marking type. The more powerful the laser, the faster the engraving or etching process will be.
There is a wide range of materials used in the semiconductor industry. You have ceramics, printed circuit boards, epoxy resins/molds, and silicon integrated circuits to name a few. The big key when marking on semiconductor substrates is precision accuracy and depth control. Accuracy is required to ensure proper placement and readability of markings that are commonly smaller than 1mm in size and read by vision systems. Depth control limits the amount of particulate dust and thermal transfer to protect sensitive electronics or components.
Our 532nm Green laser marking systems are capable of meeting the standards of semiconductor marking applications. The 532nm Green wavelength is inherently cooler than that of IR lasers and provides less thermal transfer. Along with the thermal benefits of the 532nm laser, increased absorption allows for less intense laser settings, which helps with precision depth control. The 532nm lasers are capable of marking directly onto printed circuit boards without exposing the underlying copper layer. These lasers can even mark silicon wafers or integrated circuits that can only be measured in angstroms. Couple these inherent benefits with advanced optical control to create spot sizes as low as 10um, and you have the ideal laser for semiconductor applications.
Silver and Gold
Precious metals like silver and gold are very soft. Silver is a tricky material to mark as it oxidizes and tarnishes easily. Gold can be very easy to mark, requiring little power to get a good, contrasting anneal.
Each and every RMI Laser series is capable of marking on silver and gold and the ideal system for your application depends on your marking requirements. Because of the value of these substrates, engraving and etching are not common. Annealing allows the surface oxidation to create contrast, removing only a negligible amount of material.
Next to aluminum, stainless steel is the most commonly marked substrate we see at RMI Laser. It is used in virtually every industry. There are several types of steels, each with varying carbon content, hardness, and finishes. Part geometry and size also vary greatly, but all allow for a variety of marking techniques.
Each and every RMI Laser series is capable of marking on stainless steel and the ideal system for your application depends on your marking requirements. Stainless steel lends itself to every laser marking technique used today. Carbon migration or annealing is rather simple and black anneals can be achieved with low or high wattage. Etching and engraving are also easy, because the steel is absorbent and is good enough at thermal transfer to help mitigate damage. Polish marking is possible, too, but it’s a rare choice because most applications require contrast.
This lightweight super alloy is used heavily in medical and aerospace applications because of its strength, durability and limited mass. Industries that utilize this material carry heavy liability and need to ensure that the marking being performed is safe and non-damaging. Aerospace applications require heavy fatigue testing to ensure no structural damage is incurred by the titanium part by way of Heat Affected Zones (HAZ), recasting/remelt layers, or micro-cracking. Not all lasers are capable of performing such markings. For the medical industry, most titanium parts are actually placed inside of the human body permanently, or for surgical tools which will be used inside of the human body. Because of this, markings must be sterile and durable. Also, these marked parts or tools must be approved by the FDA to ensure that they are truly inert and safe for their intended use.
Each and every RMI Laser series is capable of marking on titanium and the ideal system for your application depends on your marking requirements. Titanium lends itself to all marking techniques but the best laser and technique depend on the application. The aerospace industry uses annealing to limit structural damage. Medical instruments are annealed, etched or engraved depending on the intended lifecycle and use.