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3D printing mechanical components
⚙️ Best STL files of mechanical parts to make with a 3D printer・Cults
⚙️ Best STL files of mechanical parts to make with a 3D printer
Download 3D files of mechanical creations
More than just 3D prints, you will find in this collection real projects. Each design is composed of several mechanical parts that fit together to form a functional whole. These gears allow you to animate toys, automatons or even clocks!
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PRINT-IN-PLACE SPRING LOADED BOX
Free
Mechanical Quick Grab/Release Phone Stand
Free
PRINT-IN-PLACE PHONE HOLDER - FOR SPACE?!
Free
Print in Place- Distance Measuring Roll Tool
Free
TT Furious
Free
Predator Action Pliers
Free
Multi-Color Flying Helicopter Toy
Free
Flying Sea Turtle
Free
Flying Helicopter Toy
Free
Cool Squeeze - Grip Fan
Free
Fidget Gears Revolving V2 (Print In Place!)
Free
Triple Gear
Free
Smartphone Stabilizer
Free
Clock One
Free
Predator Action Pliers Mk2
Free
Mechanical Planetarium
Free
Differential Gears
Free
Triple Axis Tourbillon
Free
Platform Jack with some modifications
Free
planetary gear
Free
Save the Whales (Kinetic Whales)
Free
Gyrotourbillon - Jaeger-LeCoutre model
Free
Gyro Winder / Watch Winder
€2. 50
Turboprop Engine
Free
Industrial Bevel Gearbox / Gear Reducer (Cutaway version)
Free
Gyrotourbillon
Free
Fidget toy keychain
€1.99
Elevated Print in Place Phone Holder!
Free
Bevel Gear Toy Set 17/51T or 3:1 Ratio
Free
Christian Huygens 3D printed clock
Free
775 motor gear
Free
Industrial Spur Gearbox / Gear Reducer (Cutaway version)
Free
Planetary Gear Module Part 1
Free
Mechanical Gripper May 2019
Free
Jet Engine
Free
Eolienne Wind turbine
€5
The Humble Velocipede
Free
SAKURA Gear ring
Free
Hummingbird
Free
Deadbolt Combination Lock
Free
Shredder V8 Gears
Free
Jet Engine, 2-Spool, Current
Free
Platform Jack [Fully Assembled, No Supports]
Free
A Motorized Shark
Free
Crazy Cogs - Gear Play Set
Free
Gear Keychain
Free
Jet Engine, Geared Turbofan (GTF)
Free
Math Gear(s)
Free
7-Segments
Mechanical Planetarium
PRINT-IN-PLACE SPRING LOADED BOX
PRINT-IN-PLACE SPRING LOADED BOX
Here is our selection of the best mechanical STL files, all of these beautiful creations are from the Cults 3D file library and are easily 3D printable.
All you have to do is print the different STL parts of these projects, assemble them and enjoy the super satisfying result of a perfectly working mechanism !
For a long time, 3D printing was limited to very simple objects, but 3D designers are increasingly proposing complex creations - which certainly require some work after printing - but which allow for the realization of very successful projects. These mechanisms are most often presented in the form of simple gears, but in some cases, the addition of multiple gears and especially their particular shape can generate real small dioramas.
3D printing is obviously an incredible technical achievement, but projects with gears add an extra layer: assembly. So you will really have your hands in the project and will have a real feeling of satisfaction once the assembly is finished. Then, just turn on the mechanism and enjoy the rendering!
3D Printing Concepts and 3D Printer Parts
3D Printer Parts
Extruders
Extruders are a crucial component in 3D printers.
In simple terms, the extruder is the tool that holds the filament in place and controls the amount that is fed into a Hot-end. One key point is to highlight that hot-ends are not the same as an extruder, but rather they are attached to it and they are the main location that is tasked with the melting process.
Extruders come with a stepper motor that allows for the filament to be fed through. Additionally, some form of gearing and hobbed shaft to hold the filament in place, a fan in some cases, a heat sink for better temperature regulation and finally the hot end.
Extruders can come as a dual setup or a single extruder. Dual extruders give the option of printing with a support material that is used to hold up certain designs which may require it due to the complexity of the object. Additionally, a dual extruder system can be independent or dependent. This means that with a independent system, you have the additional option of being able to print with multiple materials within a single object and not just being able to print with support material which is only available with standard dual extrusion systems.
There are two types of extruders that are used in the 3D printing industry. These are Direct Extruders and Bowden. The main difference between the two is that in Direct Extruders, the motor that drives the filament and the hot end are directly attached to the extruder body. Bowden on the other hand includes a separation tube between the extruder and hot end, where the extruder, including the motor and other components can be attached to the printer chassis.
Each type has its own drawbacks and benefits.
Direct Drive:
Advantage: Can print with a wider variety of materials because the hot end and extruder are close to each other.This leads to better control with the extrusion process.
Disadvantage: Because both parts are attached, this leads to issues when printing at high speeds since the overall mass is higher.
Bowden A:
Advantage: Lower issues due to less mass needing to be moved.
Disadvantage: Problems with printing with certain filaments like flexible materials.
Print bed
A print bed is the part that the 3d printed object rests on during the printing process. As each layer is extruded, the print bed moves down to allow for the next layering step. Although being simple, a print bed is an important part of a 3D printer. Although a relatively easy process, 3d printing does require some careful calibration to ensure that you get a perfect print without deformities. Therefore, the most important step is to ensure that you print the first layer accurately.
The first layer is important because any mistakes in this layer will be magnified to the overall structure of the intended part. The first layer indicates if the print bed is levelled correctly, it indicates that you have the correct extrusion settings such as amount, temperature and more.
A print bed should provide sufficient adhesion to the molten material, ensuring the object adheres to the bed.
This is key because the extruders are moving components and if the plastic doesn’t properly attach to the bed, the movement will create many issues to the first layer as it cools. Additionally, due to cooling, the plastic can deform which is known as warping, by peeling away from the bed floor.
Which type of print Bed?
Print beds can come in a number of materials but the two most common are aluminium and glass. These both offer a smooth surface for the object to rest on, however because of the surface, this can cause adhesion issues. To combat this, print beds can come heated or a user can apply a gluing agent to help with bed adhesion which is strong enough to hold the object, but also allow for easier removal once printed.
Gluing agents come in various forms, from a standard glue stick, hairspray and special sheets you attach on to the print bed. These options are all relatively cheap and it is recommended to always use some form of agent to reduce issues that can occur.
Heated print beds reduce the chance of the object warping since they provide heat to the first layer, ensuring no random pockets cool faster than others. Aluminium beds offer the most uniform heat distribution, but aluminium itself expands significantly as its temperature increases which can cause problems. Glass on the other hand doesn’t expand easily but it doesn’t offer the same temperature distribution meaning some areas are cooler than others. One way to circumvent these potential issues is to use a print bed with both materials, where the aluminium rests below the glass, providing uniform heat through out the glass plate, which doesn’t expand as much as the aluminium.
Hot Ends
A hot end is where the filament is melted then extruded through a nozzle. Hot ends come in many forms but the standard ones consist of a feed tube, a heatsink, thermal barrier tube with a heat-break, heat-block and the nozzle in that order.
The feed tube guides the filament from the extruder, down through the heatsink and thermal barrier tube.
The purpose of the heat sink and thermal barrier tube is twofold. The top most part of the thermal barrier tube is located within the heatsink and feeds the filament through. The bottom section of the thermal barrier tube is connected to the heat block where the filament is melted. Just before it however, the thermal tube is thinner and this area is called the heat-break. This is all done to ensure that before the filament reaches the heat block, that the temperature is lower, prevent melting of the filament before it reaches the heat block by a process called heat creep. The heat-break creates a sudden change in temperature so as to better have control of the melting process.
Enclosure
An enclosure is having a sealed off printing environment for the 3D printing process. The reasoning for this is for safety but also to create better temperature management to ensure better printing results. Due to the nature of utilising high-temperature processes, issues with overheating plastics can create fumes on select printing materials, such as ABS.
An enclosure ensures you have less particles in the air, but additionally, a printer can include a HEPA filter that can reduce these dangerous particles and allow the printer to be used safely in for example in an office environment.
Furthermore, an enclosure ensures that the internal ambient temperature of the printer is stable which plays a major roll in reducing printing issues such as warping and cracking.
Filament
A filament in the context of Filament Fused Fabrication (Fused Deposition Modelling) is a coil of thermoplastic or a composite that comes in various diameters. The filament is fed through the printer and then into the extruders where it is melted then extruded. Unlike other 3D printing techniques, the filament is solid and cost-effective for many organisations. Additionally, it is the safest printing 3d printing technique which is a major factor in its popularity.
Materials that are available are various plastics, like PLA, PETG and composites where plastic is mixed in with other materials like wood to allow for a variety of possible 3D printing parts.
FFF has the largest selection of materials and each year, more materials are added to the roster. This gives FDM a greater edge than other 3D printing techniques in terms of versatility. However large the selection of materials, currently there isn’t a major metal filament available and the ones that are available require extra steps like sintering to finish a metal 3d printed part.
3D Printing Process
Layer height
Layer height is the thickness of each 3D printed layer of an object. This can also be called the Z Resolution which is referring to the process of creating each layer as the print bed moves down to allows for another layer.
A smaller layer height yields better quality objects with stronger strength properties. This is due to better interlayer adhesion, reducing gaps and creating a smoother overall finish for the object. This is most apparent when printing curves, where you can see the stepping of the edges.
Smaller layer heights however require more printing time, therefore the selection showed have careful thought before the printing process begins.
Print Speed
Print speed refers the traveling speed of the extruders as they travel during the printing process. It is express in mm/s and also determines the print quality of an object. A balance must be met in terms of print speed when making adjustment before the printing process because it does affect other settings. For example, faster speed will require more temperature awareness since increasing the speed will usually reduce the quality of the print. As a side note, we must not confuse print speed with travel speed, which is the speed at which the extruders when not directing printing.
Software Terms
Slicer
Slicing software is a category of 3D printing software that is used to convert a basic 3D computer object into something that the printer can understand and print accurately. There are various options of slicing software but they all work with the same output. They can take a 3D object, convert the surface into miniature triangles, that come together to make the object.
The amount of these triangles also determines the accuracy and detail in the 3D object that can be printed. Within the application, you can get detail controls about the printer, how to print the object, orientation, material settings and all settings possible for the 3D printer.
After setting the desired parameters, the slicer software can then slice the 3D object into the desired layer height and visualized the printing process. When this is completed, the object file is then converted into G-code, which a data type used in many manufacturing processes that stores information about how to print or in the case of CNC machine, how to mill an object. This G-code is what drives the extruders in the 3D printer to accurately create the object.
Infill
Slicing software gives you the option to print a fully solid object, or a hollow one and everything in-between. This is accomplished through setting the infill amount. This is usually how the internal structure of an object is to be printed and the settings range from 5% infill to 100%.
Furthermore, you get four main infill pattern types which are honeycomb, wiggle, rectangle and triangular.
Honeycomb offers the greatest strength with minimum material, triangle offers better lateral load strength, which gives the outer shell of the object better strength to handle horizontal forces applied to the object. Wiggle is mainly used for flexible materials and rectangular doesn’t have any specific advantages.
Skirts and Brims
Brims, skirts and rafts are parts that at are used to create better bed adhesion for the 3D printed object before the printing process and to check that everything is set-up correctly.
A skirt is an outline of the print area of the object, but doesn’t directly touch the object. It is used as a primer, to check whether there is excess material in the nozzles, that they are calibrated correctly and to ensure consistent material flow.
A brim is directly attached to the object, but goes a little further out and involves more outlines than the skirt.
Its main purpose is to hold the object and to ensure the first layer is printed correctly.
Common Troubleshooting Terms
Warping
Warping can be described as the shrinkage of a 3D printed object at the corners of the base, mainly attributed to temperature changes. Warping is due to the process of non-uniform cooling where certain printing layers cool faster than the heated parts. When this occurs, the cooler layers end up distorting the objects geometry since cooling causes shrinkage and this action affects the immediate molten layers. As the areas cool and harden, they pull on other layers as cooling increases. The main reason for warping is heated thermoplastics need uniformed cooling after being extruded to allow an object to accurately settle while maintaining the desired geometry. If the printing bed is not heated or the ambient temperature of the print chamber is not modulated then this leads to different cooling rates. To prevent warping issues, ensure that the FFF 3d printer has a heated bed with a metal plate.
This distributes the heat throughout the bed and means a more uniformed temperature distribution. This will minimize the effects of warping in the first layers of the object.
Cracking
Cracking is caused by the same issue as warping, being the non-uniform cooling of a printed object. The difference of cracking from warping is cracking occurs at different locations in the printed object. To offset the possibility of cracking, a printer with an enclosure allows to eliminate the ambient temperature fluctuations that may occur that could lead to cracking of a 3D printed object.
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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:
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Stainless steel (316L, 304L , 17-4PH, 15-5PH, 420, 254, Ph2, GP1, 630, 410).
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Tool steel (D2, M2, h23, h21, MS1, 1.2709).
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Low alloy steel (4140).
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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 tools.
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.
