Manufacturing of intricate parts in sectors such as medicine, automotive, military, industrial production, and aeronautics, calls for high-precision and innovative Additive Layer Manufacturing(ALM)technology. One such technology is Electron Beam Melting(EBM), or simply EBM 3D printing.
What does EBM 3D printing entail? This post has the answers.
1. What is Electron Beam Melting?
Electron Beam Melting is a powder bed fusion process where a metal part is produced using a 3D printing technology to melt layers of specific metal powder with the help of a high-temperature beam of electrons and then join them in consecutive solid layers to form a complete component.
1.1 EBM 3D Printing – Development History
You may be wondering how EBM started and developed. The history of EBM 3D printing started with German physicist, Dr. Karl-Heinz Steigerwald who invented electron beam technology.
He successfully developed the first operating electron beam machine in 1952. By the beginning of 1990, a German company, H.C. Starck GmbH had begun using EBM technology to produce a wide range of industry parts.
Arcam, a German company in collaboration with Chalmers University of Technology jointly patented EBM technology in 1993.
Four years later, EBM 3D printing became commercialized after a new company, Arcam AB, was formed. In 2016, GE successfully acquired Arcam AB and is currently the EBM 3D printing technology provider.
1.2 Comparing EBM with Selective Laser Melting(SLM)
You will notice that EBM is a powder bed fusion technology with some similarities with Selective Laser Melting (SLM) and Laser Powder Bed Fusion(LPBF) Technology.
However, there are some key differences worth knowing.
2. EBM vs SLM – Similarities & Differences
Below is a table comparing both the differences and similarities between Electron Beam Melting and Selective Laser Melting Technologies:
| COMPARISONS | EBM vs SLM | ||
| Similarities | Electron Beam Melting | Selective Laser Melting | |
| Both are powder-bed fusion technologies used in additive manufacturing | |||
| Production materials must be in powder form | |||
| Materials are fused in consecutive layers during production | |||
| Both may require support structures during the production process | |||
| After 3D printing, produced parts need time for cooling | |||
| Differences | In EBM, metal melting is accomplished by a high-energy beam of electrons | Melting energy is from Carbon dioxide(CO2) laser | |
| Specific conductive metal powders are used as the production material | Uses thermoplastic polymers as the production powder material | ||
| EBM has a limited range of materials to choose from and therefore, restricts the type of parts you can produce. | Has a wide range of material options allowing you to produce a wide range of parts. | ||
| EBM has lower production accuracy and resolution | Production accuracy and resolution are high | ||
| EBM generates a wider beam for faster component printing or production | A single-beam SLM solution is not as fast as EBM but there are options for machines with one, four, and twelve beams for increased production speed | ||
| EAB 3D printing takes place in a vacuum chamber making the setup process complex. | Does not require a vacuum environment but instead an inert gas chamber at atmospheric pressure | ||
| Requires a higher powder layer height of about 70 microns | The powder layer height is lower and ranges from 20-50 microns | ||
| Has a low print volume which is cylindrical – 350 mm ( D) x 430 (H )mm | Has a higher print volume measuring – 600 mm X 600 mm X 600 mm | ||
3. Electron Beam Melting – Materials Used
EBM technology works with only a few conductive powder metals. The most commonly used metals are Titanium and Cobalt alloys.
Based on your desired component and properties, here is a list of metal materials you can use with EBM:
- Nickel Alloys
- Copper
- Tantalum
- Tool Steel
- Stainless steel
- Cobalt Chrome,
- Tungsten carbide
4. EBM – Which 3D Printer Do You Require?
EBM 3D printing is a proprietary technology. It is solely provided by Arcam AB which is currently under the control of General Electric (GE)
Therefore, the commercially used EBM 3D printers are only Arcam EBM machines
To ensure you get high-quality components and maintain high production efficiency, it is important that you only engage technicians who are highly skilled in 3D printing.
5. Electron Melting 3D Printing Process
Transformative technology—Electron Beam Melting (EBM)
Before you begin your Electron Beam Melting process, you need to have all the necessary materials or components which we discuss later in this post.
For the successful production of your EBM 3D parts, the following processes are involved.
5.0.1 Design Modeling
In this initial stage, you can either create your 3D design or get a professionally completed design of a component from a client.
The design is done with suitable 3D modeling software.
If you have or have been presented with an original project which is free from defects, you can scan it to get its printable 3D image.
5.0.2 3D Model Slicing
Because EBM printers work on layers, you need to slice your 3D design into printable layers. This is easily achieved by using a special slicing tool or application.
5.0.3 EBM Setup – Material Preparation
This involved preparing the most suitable powder and pouring it into a build plate enclosed by the vacuum chamber.
5.0.4 The Heating Process
Material heating is accomplished by a high-energy electron beam focused on the built plate and which causes the powder to melt.
5.0.5 Surface Scanning
An electron beam scans the outer layer of the metal powder to form a 3D shape. This is achieved by the beam melting the powder layer while binding them together to form the desired upper 3D component layer.
5.0.6 Successive Parts Layer Building
The electron beam continues with its scanning process layer by layer until all parts of the 3D design are completed. This is achieved because each completed upper layer shape is fused to the next and ultimately, the final layer.
5.0.7 The Cooling Process
When all layers of the 3D shape have been created and joined, both the build plate and the printed shape or component are cooled to solidify the 3D shape. The cooling process also helps in strengthening the created part.
5.0.8 Support Structures ( If Any)
If your 3D design or model requires other components to keep it stable, then these will also be printed in layers just as the main part.
5.0.9 Post-Production Processing
In this stage, you remove any unwanted structures or material that may be part of your already-printed component
5.1.0 Part Finishing
Based on the requirement, you may decide to give your part the final finish. This can be in the form of either painting, smoothing, polishing, or heat treatment
5.1.1 Quality Control (QC)
To ensure that the final 3D printed part is of the desired quality standard, quality control assessment is critical.
6. Advantages & Disadvantages Electron Beam Melting
As with other additive manufacturing processes, EBM has both its pros and cons. Let’s explore these further
6.1. Advantages
The following are some of the many advantages you will derive from embarrassing electron beam melting technology:
6.1.0.1 High Energy Source – Suitable for large-size Metal Powder
Compared with other additive manufacturing processes, EBM technology is known for its high energy source.
Therefore, this makes it easier and safer to produce parts using thicker powder particles as fine powder may be hazardous.
6.1.0.2 Effective Thermal Stress Management
Because EBM is a high-temperature process, heat treatment is not necessary during post-production processing
The technology ensures excellent heat management which ensures your parts are not distorted.
6.1.0.3 High Operational Speed – Reduce Lead Time
Electron Beam melting 3D printing operates at a high speed. Therefore, your production of parts will be fast leading to reduced lead time for certain parts.
6.1.0.4 High Precision Capability
With EBM 3D printing, you can easily create high-precision components or parts that would be very difficult to achieve by other traditional methods.
6.1.0.5 Efficiency in Energy Consumption
Compared to other additive manufacturing processes, EBM 3D printing boasts the lowest Specific Energy Consumption.
Therefore, it will enhance your manufacturing efficiency while lowering your production cost.
6.1.0.6 Manufacturing Versatility
With EBM technology, you can produce a wide range of components for different industries. This versatility makes it ideal for the production of complex items such as medical, aerospace, or electronic part among others.
6.1.0.7 Allows For Automation
Depending on the desired scale of production, you can integrate your 3D EBM printers components modeling software, printing, and post-printing processes for a fully automated and efficient parts production process.
6.1.0.8 Produces Detailed & Complex Parts
You will find the manufacturing of detailed and intricate components much easier with EBM technology compared to other additive manufacturing processes.
6.1.0.9 Uniformity of Produced Parts
EBM manufacturing technique produces parts that are uniform because of their high-precision level.
Therefore, you will not experience manufacturing losses linked to the production of defective, or rejectable parts.
6.1.1.1 Efficiency in Material Use
EBM 3D printing process produces very little waste. Further, the metal powder that remains after the formation of a component can still be used for new part production for enhanced cost-effectiveness and efficiency.
6.1.1.2 Environmentally Friendly
Because EBM technology uses less energy, fewer materials, and produces less waste, it is an ideal option if you are looking for an environmentally friendly additive manufacturing technology.
6.1.1.3 Customization Flexibility or Design Freedom
With Electron Beam printing technology, there is no boundary when it comes to the customization or design of components to suit your customers’ application requirements.
6.1.1.4 Production of High-Strength Products
Because EBM 3D printing requires metal as the production material, its produced parts are strong and durable.
6.2 Disadvantages
Despite having several advantages, EBM 3D printing technology also has the following disadvantages or drawbacks:
6.2.0.1 It is a Costly Technology
Electron Beam Melting technology requires that you invest in a specialized 3D printing machine and costly materials.
For instance, a standard EBM 3D printer can cost you hundreds of dollars. Further, the production process is labor-intensive and requires a highly skilled technician.
6.2.0.2 Complex To Setup Hardware and Software
Setting up both the hardware and software for the Electron Beam Melting 3D printing process is complex.
This is because you need to precisely configure or control several parameters such as temperature and pressure to produce high-quality components.
6.2.0.3 Limitation of Materials
Production of parts through the Electron Beam Melting process is limited to only specific metals. Therefore, both the quantity and types of parts you can produce are limited.
Again, for quality products, the materials powders have to be of high quality and adequately tested to ascertain that they fulfill the desired standards.
Further, the electron beam produced by your EBM 3D printer has to be suitable for your printing machine and the component’s provided characteristics.
6.2.0.4 Rough Surface Finish – Extended Post-Production Processes
Because the Electron Beam Melting process requires a dense layer of metal powder, produced components do not come with smooth surfaces. This is because the thick layer affects the printing accuracy.
Therefore, you have to spend more time and resources in post-processing to obtain the desired high-quality surface finish.
6.2.0.5 Low Production Volume
If you are keen on large-scale parts production, the Electron Beam Melting process will not be a suitable option.
This is because the process cannot be easily optimized. Your production volume will, therefore, remain low.
For large-volume manufacturing, you have to integrate several 3D printers with other production and post-production processes for an automated system.
6.2.0.6 Extended Cooling Time
After the formation of parts through EBM, more time is required for the 3D-printed product to be effectively cooled to avoid cracks developing or parts warping.
And so, because this takes place within the machine, you may have to wait longer before your part is ready for other post-production processes.
6.2.0.7 Metal Powder Is Hazards
The metal powder used in EBM 3D printing process may prove hazardous especially if made from fine particles. They may prove toxic when inhaled.
Therefore you must take the necessary safety measures when handling the materials.
6.2.0.8 The Challenge in Powder Removal
After part printing, the removal of powder especially from very intricate parts can be challenging.
And so your post-production processing steps may require more specialized equipment to ensure that your parts are free from metal powder.
7. Part & Functions of Electron Beam Melting Machine
Below are the main parts of the EBM 3D printing machine that you need to know, and their roles during the manufacturing process:
7.1.0.1 Machine Control System
This is a computer software solution that your 3D printing technician can program to control the operations of the 3D printing system.
7.1.0.2 Power supply
The Power Supply unit of the EBM machine provides the desired power that your electron beam gun needs for its effective operation. It also provides the required operational power for machine parts.
7.1.0.3 Temperature Monitoring System
Configuration of the right temperature is critical for EBM 3D printing process.
Therefore, the temperature monitoring system ensures that temperature levels within different sections such as the vacuum chamber or electron beam gun are kept at a suitable level.
This ensures efficient machine operation as low temperatures can have adverse quality effects.
7.1.0.4 Electron beam gun
This section is responsible for emitting the desired high-energy electron beam for heating and melting the metal powder within the vacuum enclosure.
7.1.0.5 Focus Lens
The focus lens helps in precisely directing and narrowing the electron beam to the right section of a component for its accurate production, or 3D printing.
7.1.0.6 EBD Power Hopper
This is a mechanically operated dispensing unit that helps you deliver metal powder into the powder bed ready for 3D printing.
7.1.0.7 Vacuum Enclosure
A vacuum chamber where your metal powder is collected from the hopper for parts production. It helps in trapping and extracting fumes that form during high-temperature parts production.
A special vacuum pump is linked to the vacuum chamber to facilitate the extraction of trapped gases.
The vacuum ensures precise melting of the metal powder and also protects the powder from possible oxidation during the heating and melting process. And so it keeps the created parts free from possible contamination.
7.1.0.8 Cooling system
This can either be a water or air cooling system that during EBM 3D printing process, ensures that after melting, your metal powder is cooled effectively either during the printing process
7.1.0.9 Magnetic Field Foils
Magnetic field coils form a protective magnetic field around the electron beam gun and other surrounding sections to ensure their stable performance.
It also helps in keeping the electron beam focused on the metal powder inside the vacuum enclosure for effective 3D printing of parts.
8. Applications of Electron Beam Melting Technology
Here are some of the areas where Electron Beam additive manufacturing is widely applied:
8.1 Medical Applications
The medical sector is yet another area you will find Electron Beam Additive Manufacturing technology widely used in producing a wide range of high-precision medical devices.
These devices include but are not limited to the custom production of hip replacements, canine knee replacements, oral implants, and prosthetics among others.
8.2 Airspace Sector
Airespace is yet another area where the use of EBM technology has continued to soar. For instance, engine nozzles, landing gear parts, impellers, fuel chambers, and other parts of rocket or jet engines are made using Electron Beam Melting technology.
8.3 Military Sector Applications
Production and fabrication of various high-precision military equipment including weapons and aircraft is made possible through an electron beam additive manufacturing process.
8.4 Automotive Industry
Within the automotive industry, EBM technology is used to produce engine parts or custom high-precision parts such as turbochargers, and compressor wheels. You can also use the technology to produce replacement components, or for joining parts.
8.5 Welding Industry
EBM technology is widely used in the welding industry to join metal parts without distortion risks.
8.6 Jewelery Manufacture
Because EBM technology can produce complex parts, it is used within the jewelery manufacturing sector to create more unique and attractive jewelery products.
All you need is suitable jewelery design software for a successful 3D printing of your jewelery collections.
8.7 Research Programs
Some research programs require products with complex shapes or designs. There are also instances where prototypes are required for testing purposes. All these are made possible by EBM 3D printing technology
9. Conclusion
Electron Beam Melting (EBM) technology is an innovative method of 3D printing that is used to develop a wide range of complex industry components. Its application especially in the aerospace and medical sector continues to be on the rise.
As with other additive layer manufacturing processes, electron beam melting has several advantages as well as drawbacks.
Therefore, choosing EBM as your powder bed fusion option should be based on your specific requirements and cost analysis.
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