3D printing with metal filament

Ultimate Materials Guide - 3D Printing with Metal Filament

Overview

Metal filled filaments contain very fine metal powder such as Copper, Bronze, Brass, and Stainless Steel. The percentage of metal powder infused in each filament can vary depending on the manufacturer. The presence of this metal powder makes the filament much heavier than standard plastics. This means that the parts printed with metal-filled PLA will weigh significantly more than ones from the standard PLA, despite using the same settings and consuming the same amount of material. Metal filled filaments also tend to be very abrasive as they are extruded through the hotend. A standard brass nozzle will be too soft and will quickly wear down. Be sure to upgrade to a wear resistant nozzle in order to print this filament effectively. There are other metal-like filaments in the market that may just have metallic coloring added to the filament. These filaments do not contain any actual metal powder, so they do not share many of the same benefits of the true metallic filaments. This article will focus on materials that contain actual metal powders for a realistic metallic weight and feel.

Metallic finish is aesthetically appealing
Does not need high-temperature extruder
Heavier than standard filaments

Requires a wear-resistant nozzle
Printed parts are very brittle
Very poor bridging and overhangs
Can cause partial clogs over time
Expensive

Hardware Requirements

Before 3D printing with metal filled filament make sure your 3D printer meets the hardware requirements listed below to ensure the best print quality.

Bed

Temperature: 45-60 °C
Heated Bed Optional
Enclosure Not Required

Build Surface

Painter’s Tape
Glue Stick
PEI

Extruder

Temperature: 190-220 °C
Requires Wear Resistant Hardened Steel Nozzle

Cooling

Part Cooling Fan Required

Best Practices

These tips will help you reduce the chances of common 3D printing issues associated with metal filled filaments such as clogging, the nozzle wearing down, poor bridging, and blobs left on the surface of the print.

Use Wear-Resistant Nozzles

Most 3D printers ship with brass nozzles that are relatively soft. Since metals can be abrasive in general, brass nozzles can easily wear out when used with metal filled filaments. Upgrading to a wear-resistant nozzle will help reduce the wear significantly. Another aspect to consider while upgrading is the nozzle size. Although it is possible to print with standard 0.4mm nozzles, metal particles tend to clump around the orifice and can cause clogging over extended periods of use. Nozzle sizes of 0.5 – 0.6 mm seem to work better for metal filled filaments. It is also good to periodically check the nozzle orifice for any visible wear. Worn out nozzles can otherwise result in inconsistent extrusion and reduced overall quality of the printed parts.

Be Aware of Bridging Limitations

Metal filled filaments are quite heavy, which has an impact on their bridging performance. When the molten plastic is extruded across either side of the bridge, it droops excessively and eventually breaks before it can complete the bridge. This means that parts with lots of large bridging regions will be very difficult to print.
Simplify3D Version 4.0 added several new features related to bridging, including one that allows you to completely customize the direction of this bridging fill. If you have a part that requires bridging and there is no way to avoid it, you might find that there is a specific fill angle that will work best for this material. The software also allows you to customize the exact speed and extrusion rate used for the bridges, so you can experiment to find what works best for your material. Other successful methods would be to add support structures to support any potential overhangs, or consider using a dual extrusion system with a dissolvable support structure such as PVA. Simplify3D includes a feature called Dense Supports, which allows you to use this PVA material very sparingly, only at the interface between the supports and the part, so this can be a great option as well.

Check the Filament Path for Sharp Bends

Metal filaments are very brittle in general. This affects the final parts, but it also applies to the raw filament itself which needs to be pulled into the printer as it is extruded. If you follow the filament path from the spool, all the way to the extruder, check for any sharp angles or curves which may put too much stress on the filament. We found that many printers included sharp bends that had a tendency to cause the filament to snap in the middle of printing. You may notice this happens more as the toolhead moves around during the print, since different toolhead positions may put more stress on the filament as it bends to move to the new location. One great way to avoid this is the change the location where the filament spool is mounted. Start by mounting the spool on top of the printer and try to minimize the distance from the spool to the extruder.
Additionally, a strong filament guide tube that limits the bend in the filament path will prevent most breakages.

Tune Your Retraction Settings

Like wood filled and other composites materials, retractions with metal filled filaments can be rather challenging. The presence of metal powder makes it difficult for the nozzle to contain the suction pressure in the melt chamber during retraction. This will frequently lead to blobs at the beginning and end of each printed segment, where the extruder was trying to start or stop the plastic extrusion. Simplify3D has several features that can be a big help in this situation. The first is a unique feature called Coasting, which will automatically reduce the pressure in the nozzle right before the end of a print segment. This greatly reduces oozing when moving to the next print segment, so it can be a great option to consider. You can also try setting the “extra restart distance” to a negative value of -0.1 or -0.2mm, as this can help with the blobs that may form at the start of each segment. For more tips on how to reduce these blobs, please refer to our Print Quality Guide: How to Reduce Blobs and Zits.

Pro-Tips

To prevent the chances of clogging, you can greatly reduce the number of retractions in Simplify3D by enabling the “Only retract when crossing open spaces” option or disabling “Force retraction between layers”. Both of these settings can be found on the Advanced tab of your process settings.
Due to the heavy nature of this material, metal filled filaments typically do quite poorly when printing overhangs or bridges. To reduce the number of overhangs required for your print, try reducing the layer height to 0.1 or 0.15mm. This can significantly improve overhang performance.

Get Started with Metal Filled Filaments

There are many unique applications for these specialty filaments. We’ve put together a list of common applications, sample projects, and even popular brands of filament to help you get started.

Common Applications

Sculptures and Busts
Replicas for Museums
Jewelry

Sample Projects

Bull
Minerva
Anvil
Nefertiti

Popular Brands

ColorFabb Brassfill, Bronzefill, Steelfill, CopperFil
Protopasta Composite PLA – Magnetic Iron, Polishable Stainless steel
FormFutura MetalFil

FFF Metal 3D Printing for the Lab, Classroom or Studio

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Make full metal parts in-house
No need to send your parts away

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Go Deeper with the Basics

The basics of getting started and working with Metal FilamentWatch as Integza uses Stainless Steel filament to 3D print an aerospike Rocket Nozzle.

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Steel 3D Printing - A Quick Guide / Sudo Null IT News

Any metal 3D printing technology can print with steel. This is the most popular material. But which steel grades and which technology is best for your application? Will printed steel parts really be as strong and durable as traditionally made parts?

Let's see how a 3D printed steel part is revolutionizing manufacturing and opening doors to new applications in aerospace, medical equipment, automotive, tool making, heavy industry, architecture and more. In addition, more affordable desktop printers are expanding the scope and scope of real steel 3D printed parts.

Strength of steel printed parts.

Cast steel part (left), 3D printed version (center). On the right, a fully 3D printed hinge requires no assembly.

(Source: Desktop Metal)

The most common question when it comes to a 3D printed metal model is "Will it be as strong as a forged or cast part?" ?". The short answer is yes... and no.

3D printed steel parts can be just as strong, and sometimes even stronger, than those made in the traditional way. It depends on many factors such as: end use, type of steel, choice of 3D printing method, post-processing and shape of the part. Also, the comparison depends on which of the strength characteristics you focus on: tensile strength, static load strength, fatigue strength, etc.

Parts printed from steel are used in the aerospace industry, for the military, and also, for example, for the manufacture of a footbridge, shown below. Therefore, the strength of printed products is beyond doubt, but let's take a closer look.

Queen Maxima of the Netherlands officially opens a 3D printed metal bridge. Photo by Adriaande Groot (Source: MX3D)

A 3D printed or laser powder sintered (LPBF) steel part has a finer grain structure than cast metal products. This provides better tensile strength characteristics, but in other respects the cast parts are currently still stronger. Most often, LPBF 3D printing is used to replace cast components, but in some cases, 3D printed components can replace forged parts.

One study showed that, under certain conditions, stainless steel parts made using LPBF 3D printers were three times stronger than parts made from the same steel using the traditional method.

In experiments comparing 3D printed steel parts to traditionally made steel parts, researchers create identical parts using two methods and compare their performance. However, head-to-head comparison of details is only part of the big picture.

The main advantage of printing with steel is not only its strength, but also the unique ability to create internal channels and lattice fillings in parts, which is impossible using traditional manufacturing methods. Metal 3D printing makes it possible to produce parts faster than traditional production, since this method does not require the use of special equipment and tools, it allows you to create assemblies as a whole, eliminating the need for subsequent assembly and welding. Designing a printed part usually means that less metal is needed to make it, and therefore less weight, for the same strength.

MX3D Wire Arc Additive Manufacturing (WAAM) printed steel architectural support (Source: MX3D)

Steel 3D printing is also more stable and cost effective as it reduces waste. When using subtractive manufacturing methods, such as CNC machining, you make a part by cutting it out of a large one, with a lot of waste. With additive manufacturing, you only use the material you need to make the finished product.

Steel 3D printing is not intended to replace traditional methods in all areas, but it may be a better choice for a wide range of applications. Particularly when the required parts are unique and designed for specific applications, such as rocket engines, racing cars or the oil and gas industry. 3D printing is the fastest and most flexible technology for mass production and prototype production. For military and industrial applications, steel 3D printing is a faster and more efficient way to create individual parts for vehicles and machines. Stainless steel 3D printing is rapidly finding applications in medicine to create unique surgical instruments and implants.

If you know what characteristics your final product should have (tensile strength, compressive strength, hardness, density, etc.), then all these parameters can be incorporated into the product at the production stage.

Types of steel for 3D printing

Metal powder is the most used metal material for 3D printing (Source: GKN Additive)

There are thousands of different grades of steels and alloys with different mechanical properties, used in traditional manufacturing but in 3D printing there are only a few dozen of them, and some of them are unique, created specifically for this technology. Among the steel options, the following can be distinguished:

Stainless steel (316L, 304L , 17-4PH, 15-5PH, 420, 254, Ph2, GP1, 630, 410).
Tool steel (D2, M2, h23, h21, MS1, 1.2709).
Low alloy steel (4140).
Structural alloyed (20MnCr5).

Recently, unique alloys have been developed specifically for 3D printing, designed to solve the problems that occur with classical production methods.

For example, 3D printer manufacturer Desktop Metal released a patented stainless steel in 2022 that the company says combines the tensile strength, ductility, and corrosion resistance of 13-8 PH stainless steel, combined with the hardness low alloy steel like 4140. The company says customers can go to market with this material and skip the galvanizing step to protect products from corrosion.

ExOne offers two special blends of steel and bronze that the company says allows 3D printed steel parts to achieve increased corrosion resistance while being easy to machine and polish.

While most of the metal powders used in 3D printing are similar to those used for other manufacturing methods, their numbers are on the rise as more companies adopt the technology. Some metal powder manufacturers, such as GKN, also make custom powders for specific 3D printing applications.

How to print with steel

The strength, properties and applications of 3D printed steel products largely depend on which 3D printing technology you use. Some methods produce stronger parts, other methods provide better hardness or abrasion resistance, and some technologies are simply very fast.

Below are the main metal 3D printing methods, their properties and some of the most common application examples.

Fused Deposition Printing (FDM)

BCN3D's Epsilon printer extrudes metal filament from stainless steel (Source: BCN3D) as more printer manufacturers certify metallic filaments for use on their printers, such as Ultimaker, BCN3D, Makerbot, Raise3D. Raise3D has recently released a complete metal printing suite - Metalfuse (3D printer, debinding oven and sintering oven). This method is still much more popular for printing plastics, but with new plastic filaments filled with stainless steel powder, strong metal parts can be produced.

FDM media was once limited to thermoplastics. Companies like BASF Forward AM and The Virtual Foundry now offer metal filaments that can be used on almost any FDM printer as long as it has a hardened steel nozzle for abrasive media.

These materials are approximately 80% metal and 20% plastic. After printing, the post-processing process removes the plastic, resulting in 100% metal parts.

Due to the removal of the bonding plastic, FDM metal parts shrink during post-processing. The amount of shrinkage is constant and can be taken into account in CAD systems, which allows to obtain relatively accurate finished parts.

Forward AM's 316L Stainless Steel Ultrafuse filament produces finished parts with material properties that the company claims are comparable to injection molded metal parts.

(Source: BCN3D)

While 3D printing with metallic materials may not be suitable for demanding applications such as aerospace, the economics of producing simple metal components without critical loads on an affordable FDM printer can outweigh the impossibility of applying them in some areas.

Metal prototype parts and finished parts that will not be subjected to extreme stress are ideal uses for this technology.

Bound Metal Deposition (BMD)

Desktop Metal's Studio System 3D printer used bonded metal bars that were extruded layer by layer to form a metal part (Source: Desktop Metal)

Similar to FDM, Metal mesh deposition method (BMD) or bonded powder extrusion (BPE) is a 3D printing process based on extrusion. This method uses bonded metal rods or bonded powdered metal filaments, which consist of a much higher percentage of metal powder than the filaments used in FDM. As with FDM, post-treatment to remove the binder and heat treatment in a final sintering oven are required.

There are only a few 3D printers using this method such as Desktop Metal, Markforged and more recently 3DGence, but more companies are entering this market, so stay tuned. These printers are valued as a convenient solution for office 3D metal printing, they are more expensive than most FDM printers, but cheaper than the powder-based metal 3D printing technologies described below.

These printers use their own proprietary filament. Desktop Metal and Markforged offer four types of steel.

Ideal niches for this technology are metal prototype parts, where it is necessary to test the functionality of a part before mass production using traditional methods. Popular applications are molds, punching dies, nozzles, impellers, fasteners and heat exchangers.

For example, Shukla Medical uses Markforged's Metal X printer to print steel prototypes of its orthopedic implant removal instruments.

Laser powder sintering.

Laser powder sintering technology uses one or more lasers to melt powdered metal into a desired shape layer by layer (Source: GE Additive) metal printing. This technology is used by 80% of all metal 3D printers on the market.

This method uses powerful lasers to selectively sinter metal powder layer by layer.

LPBF 3D printers are available in a wide range of sizes, prices and laser powers. These and other characteristics affect the properties of the finished part, print speed and other parameters of the finished products.

Steel and steel alloys are the most popular material for LPBF equipment and, unlike FDM and BMD, metal powders are commercially available as they are most commonly used in traditional production methods.

LPBF is a technology that maximizes the quality of a 3D printed part. Applications include aerospace components such as monolithic thrust chambers, rocket engine components and heat exchangers, molds, tools and other applications, as well as high wear parts and surgical instruments.

Binder Jetting

Binder 3D printing technology uses metal powder and a binder to form metal parts (Sorrce: ExOne) binder, and not with a laser. During post-processing, the binder is removed.

Binder application stands out for its high printing speed compared to other 3D printing methods or traditional manufacturing, and metal parts made with this technology have material properties equivalent to those made by metal injection molding.

The number of manufacturers producing metal-bonded inkjet 3D printers is much smaller than that of LPBF machines. Leading manufacturers include ExOne, Desktop Metal, Digital Metal, GE Additive and HP.

Binder blasting is ideal for medium to high volume production of metal tools and spare parts.

In fact, HP claims that its Metal Jet 3D printer was designed specifically for mass production of 316L stainless steel products. HP has partnered with Parmatech to produce metal parts for the medical industry. Pennsylvania-based ExOne uses this technology to manufacture hard metal cutting tools and tool steels.

Electron Beam Melting (EBM)

(Source: GE Additive)

Electron Beam Melting (EBM) is another powder cladding technology. It works in a similar way to selective laser melting (SLM), but instead of using a laser as the energy source, it uses a much more powerful beam of charged particles.

The recoater moves the powder onto the printing plate and an electron beam selectively melts each layer of powder. After each layer is printed, the plate is lowered and another one is applied on top of the previous layer.

EBM can be much faster than SLM, but SLM produces smoother and more accurate pieces. The electron beam is wider than the laser beam, so EBM cannot produce the same precise parts as SLM. Another difference is that the manufacturing process takes place in a vacuum chamber, which reduces the amount of impurities in the material that can lead to defects. That is why EBM is often chosen for printing components for the aerospace, automotive, defense, petrochemical and medical implant industries.

Titanium is the most popular metal for most EBM applications, however steel can be used.

Cold Spray

(Source: Impact Innovations)

Cold spray 3D printing is done by injecting metal powders through a jet nozzle into a supersonic stream of pressurized gases such as air, nitrogen or helium. The process is called "cold" because the metal particles do not melt, but hit the metal substrate and adhere to its surface during the so-called plastic deformation.

Cold spray printed products are not prone to porosity, thermal cracking and other defects associated with melt-based technologies. This method has several advantages over other production methods. The technology is used in the military and aerospace industries around the world. For example, the US Army uses cold spray to repair the mounts of a worn Bradley 25mm steel turret gun.

In the automotive industry, cold spray steel is used for crash repairs because the high strength steel substrates in cars can be susceptible to thermal repair methods such as welding.

Direct Energy Deposition (DED) and Wire Arc Additive Manufacturing (WAAM)

WAAM Steel Parts from MX3D (Source: MX3D)

Direct Energy Deposition (DED) uses welding powder or wire that enters through a nozzle and is fed into the power source to melt the metal. A melt region is created and applied to the substrate. DED is a new process, reminiscent of an old building technology known as "cladding", in which a coating is applied to a substrate, often for thermal insulation or weather resistance. DED is useful for fabricating large objects as a whole, as well as complex geometries that require extensive machining. DED can get such parts much closer to finished than traditional CNC machining.

Because DED uses a coating process, it can be used to add complex geometries to existing steel parts, thus combining complexity with cost reduction. For example, the French company AddUp advertises a rocket nozzle that uses a preformed large 304 stainless steel hopper cone printed with an isogrid structure, usually made from a larger piece by traditional methods.

A technology related to DED is wire-arc additive manufacturing (WAAM). Instead of powder, WAAM uses a metal wire that is melted by an electric arc. The process is controlled by robotic arms. WAAM is also capable of producing large-sized metal parts, as demonstrated by the Dutch company MX3D and its nine thousand-pound 41-foot stainless steel bridge in Amsterdam, as well as an oil and gas equipment repair part, proving that parts can be made in the field.

Micro 3D printing

Micro parts printed from steel (Source: 3D MicroPrint)

Micro scale additive manufacturing, or micro 3D printing, can produce products with a resolution of a few microns (or less). There are three micro 3D printing methods to produce metal parts.

LMM (lithography-based metal fabrication) is a light-based technology that creates tiny parts from raw materials, including stainless steel, for applications such as surgical instruments and micro-mechanical parts.

Electrochemical deposition is the latest micrometal 3D printing process developed by the Swiss company Exaddon. In this process, the printing nozzle applies liquid with metal ions, creating details at the atomic level.

A third micrometal 3D printing method is microselective laser sintering, in which a layer of metal nanoparticle ink is applied to a substrate, then dried to produce a uniform layer of nanoparticles.

German researchers have successfully tested micro SLS printing of hollow microneedles using 316L stainless steel.

Metal parts from 3D Systems, Desktop Metal, MX3D and Materalise.

Metal 3D printing

Metal 3D printing can be considered one of the most enticing and technologically challenging areas of additive manufacturing. Attempts to print with metals have been made since the early days of 3D printing technologies, but in most cases they ran into technological incompatibilities. In this section, we will look at technologies that have been tested for printing both composite materials containing metals and pure metals and alloys.

1 3D inkjet printing (3DP)
2 Lamination Printing (LOM)
3 Layered welding (FDM/FFF)
4 Selective Laser Sintering (SLS) and Direct Metal Sintering (DMLS)
5 Selective laser (SLM) and electron beam melting (EBM)
6 Direct laser additive construction (CLAD)
7 Free electron beam melting (EBFȝ)

3D inkjet printing (3DP)

How 3D inkjet printers (3DP) work

Inkjet 3D printing is not only one of the oldest additive manufacturing methods, but also one of the most successful in terms of using metals as consumables . However, it is necessary to immediately clarify that this technology allows you to create only composite models due to the technological features of the process. In fact, this method allows you to create three-dimensional models from any materials that can be processed into powder. The binding of the powder is carried out using polymers. Thus, finished models cannot be called fully "metal".

At the same time, there is the possibility of converting composite models into all-metal models due to heat treatment in order to melt or burn out the binder material and sinter the metal particles. The models obtained in this way do not have high strength due to porosity. An increase in strength is possible due to the impregnation of the resulting all-metal model. For example, it is possible to impregnate a steel model with bronze to obtain a stronger structure.

Models obtained in this way, even with metal impregnation, are not used as mechanical components due to their relatively low strength, but are actively used in the jewelry and souvenir industry.

Lamination printing (LOM)

Laminating 3D printer (LOM)

models.

Metallic foil can also be used as a consumable.

The resulting models are not all-metal, as their integrity is based on the adhesive used to bond the consumable sheets.

The advantage of this technology is the relative cheapness of production and the high visual similarity of the resulting models with all-metal products. Typically, this method is used for layout.

FDM/FFF

Model made of BronzeFill before and after polishing

The most popular 3D printing method has also not bypassed the use of metals as consumables. Unfortunately, attempts to print with pure metals and alloys have so far not led to significant success. The use of refractory metals runs into quite predictable problems with the choice of materials for the construction of extruders, which, by definition, must withstand even higher temperatures.

Printing with fusible alloys (for example, tin) is possible, but does not give enough high-quality output for practical use.

Thus, in recent years, the attention of consumables developers has switched to composite materials, similar to inkjet printing. A typical example is BronzeFill, a composite material consisting of thermoplastic (details not disclosed, but apparently PLA plastic is used) and bronze powder. The resulting models have a high visual similarity with natural bronze and can even be polished to a high gloss. Unfortunately, the physical and chemical properties of finished products are limited by the parameters of the thermoplastic binder, which does not allow classifying such models as all-metal.

Nevertheless, such materials can be used not only in the creation of models, souvenirs and art objects, but also in industry. Thus, the experiments of enthusiasts have shown the possibility of creating conductors and shielding materials using thermoplastics with a metal filler. The development of this direction can make it possible to print electronic circuit boards.

Selective Laser Sintering (SLS) and Direct Metal Sintering (DMLS)

The most common method for creating all-metal 3D models involves the use of laser machines for sintering metal powder particles. This technology is referred to as Selective Laser Sintering or SLS. It should be noted that SLS is used not only for working with metals, but also with thermoplastics in powder form. In addition, metallic materials are often coated with more fusible materials to reduce the required power of laser emitters. In such cases, finished metal models require additional sintering in furnaces and impregnation to increase strength.

A variation of the SLS technology is Direct Metal Laser Sintering (DMLS), which, as the name implies, is focused on working with pure metal powders. These plants are often equipped with sealed working chambers filled with an inert gas for working with metals subject to oxidation, such as titanium. In addition, DMLS printers necessarily apply consumable heating to a point just below the melting point, which saves on the power of laser systems and speeds up the printing process.

SLS, DLMS and SLM systems

The laser sintering process begins with the application of a thin layer of heated powder to the work platform. The thickness of the applied layers corresponds to the thickness of one layer of the digital model. Then the particles are sintered between themselves and with the previous layer. Changing the trajectory of the laser beam is carried out using an electromechanical system of mirrors.

When a layer is drawn, the excess material is not removed but serves as a support for subsequent layers, which allows you to create complex shapes, including hanging elements, without the need to build additional support structures. This approach, coupled with high accuracy and resolution, makes it possible to obtain parts that require almost no machining, as well as solid parts of a level of geometric complexity that is unattainable by traditional production methods, including casting.

Laser sintering allows you to work with a wide range of metals, including steel, titanium, nickel alloys, precious materials, etc. The only drawback of the technology can be considered the porosity of the resulting models, which limits the mechanical properties and does not allow achieving strength at the level of cast analogues.

Selective laser (SLM) and electron beam melting (EBM)

Despite the high quality of the patterns produced by laser sintering, their practical application is limited by the relatively low strength due to porosity. Such products can be used for rapid prototyping, prototyping, jewelry production and many other tasks, but are of little use for the production of parts that can withstand high loads. One solution to this problem has been the conversion of direct metal laser sintering (DMLS) technology to laser melting additive manufacturing (SLM) technology. In fact, the only fundamental difference between these methods is the degree of heat treatment of the metal powder: SLM technology is based on complete melting to obtain homogeneous models that are practically indistinguishable in physical and mechanical properties from cast counterparts.

An example of a titanium implant made using electron beam melting (EBM) technology

A parallel method that has achieved excellent results is electron beam melting (EBM). At the moment, there is only one manufacturer that creates EBM printers - the Swedish company Arcam.

EBM achieves accuracy and resolution comparable to laser melting, but with some advantages. Thus, the use of electron guns makes it possible to get rid of the delicate electromechanical mirror systems used in laser systems. In addition, the manipulation of electron beams using electromagnetic fields is possible at speeds that are incomparably higher compared to electromechanical systems, which, coupled with an increase in power, makes it possible to achieve increased productivity without significantly complicating the design. Otherwise, the design of SLM and EBM printers is similar to laser metal sintering machines.

The ability to work with a wide range of metals and alloys allows you to create small batches of specialized metal parts that are almost as good as samples obtained using traditional production methods. There is no need to create additional tools and infrastructure, such as molds and furnaces. Accordingly, significant savings are possible in prototyping or small-scale production.

Laser and electron beam melting machines have been successfully used to produce items such as orthopedic titanium prostheses, gas turbine blades and jet engine injectors, among others.

Direct Laser Additive Building (CLAD)

How CLAD plants work

Not so much a 3D printing technology as a "3D repair" technology. The technology is used exclusively at the industrial level due to the complexity and relatively narrow specialization.

CLAD is based on the deposition of metal powder on damaged parts, followed by immediate welding with a laser. The positioning of the "print head" is carried out along five axes: in addition to moving in three planes, the head has the ability to change the angle of inclination and rotate around the vertical axis, which allows you to work at any angle.

Such devices are often used to repair large items, including manufacturing defects. For example, the installations of the French company BeAM are used to repair aircraft engines and other complex mechanisms.

Complete CLAD units use a sealed inert atmosphere working chamber for titanium and other oxidizable metals and alloys.

Free electron beam melting (EBFȝ)

How EBF printers work

Technology developed by NASA for use in zero gravity. Since the absence of gravity makes working with metal powders almost impossible, EBFȝ technology involves the use of metal threads.

The build process is similar to Fused Deposition 3D printing (FDM), but using an electron beam gun to fuse the consumable.

This technology will allow the creation of metal spare parts in orbit, which will significantly reduce the cost of delivering parts and provide the ability to quickly respond to emergency situations.