Everything You Need to Know About Metal Binder Jetting
Metal binder jetting technology is coming back. In the past ten years, a large number of new businesses have joined the market for binder jetting, each with a distinctive strategy. The numerous lucrative domains of application that this technology offers serve as a driving force behind these endeavours. One factor that may help the metal binder spraying process become a new approach for mass manufacturing is its great speed and accuracy.
But what innovations are fueling the technology of Metal binder jetting to success?
We'll examine Metal Binder Jetting today to see how it developed and why it's becoming a new production technology.
The origins of metal binder jetting
The Massachusetts Institute of Technology (MIT) invented an inkjet-based method for fabricating three-dimensional things from metal powders in 1993, which is when this AM technology first emerged. It's interesting to note that MIT was the first to use the phrase "3D printing" to describe the metal binder jetting technique.
An exclusive licence for the MIT technology was granted to the manufacturing business Extrude Hone Corporation in 1996. The business has since created and sold metal binder jetting systems. ProMetal RTS-300, the first 3D printer, was delivered to Motorola in 1999. Up until the early 2010s, ExOne, which was separated from Extrude Hone Corporation in 2005, was the only business providing metal binder jetting systems and services. The early MIT patents on the technology were starting to lapse around this time, opening the market to new businesses. The technology has now been reintroduced with the intention of using it effectively for manufacturing across all industries.
How does metal truss spraying work?
A liquid binder is administered selectively in metal binder jetting to layer-by-layer bind powder particles. The procedure starts with the distribution of a thin layer of powder, followed by the controlled introduction of binder droplets by print heads into the powder bed. Another coating of powder is placed while the printing plate is lowered. Until the portion is finished, the procedure is repeated. About 95% of unused powder is recycled and reusable. The pieces that have just been printed remain in a delicate green state after spraying with metal binders and need to be processed later, like painting. B. To make the portion stronger, it was sintered and infiltrated. The binder jet can be utilised with a variety of different materials, such as sand and ceramics, in addition to metals.
Post-processing steps for metal tie ejection
In conventional binder jet technique, layers of powder are coated with a liquid binder using a printhead. However, because they are initially produced in the green condition when employing binder jetting technique for additively producing metals, the parts need numerous post-processing processes. This indicates that they have poor mechanical qualities and are frequently fragile and weak. The goal of the post-processing phase, which also includes hardening, sintering, infiltration, and other finishing procedures, is to reinforce the pieces.
The green pieces become stronger after curing, making it possible to remove them from the print bed without risk. The procedure involves several hours of the pieces being hardened in an oven at about 200°C, giving them substantially better mechanical qualities.
The metal components are still rather porous even after hardening. Sintering or infiltration techniques greatly reduce the porosity of the pieces. The part is typically heated to about 100°C for 24 to 36 hours during the sintering process in a controlled environment furnace, when the binder is burnt off. As a result, a robust metal component with little porosity is produced by helping to fuse the metal particles together. Sintering, however, can cause the part to shrink unevenly and is difficult to forecast, therefore this must be taken into consideration during the design stage.
The portion needs to be penetrated to fill the gaps left by the binder burning off in order to obtain high density. Typically, molten bronze is used to fill up the remaining gaps in the portion. The mechanical characteristics of the metal item are greatly enhanced by these post-processing processes. For instance, stainless steel infiltrated with bronze can result in a final density of 95%.
To obtain aesthetically acceptable finishes, the item can optionally be polished and nickel- or gold-plated.
What are the reasons for metal binder jetting as a production technology?
Metal binder jetting is more convenient to employ for industrial applications because to a number of distinctive benefits.
First, spraying the binder prevents the metal powder from melting during the printing process, which eliminates issues caused by the buildup of residual stress. Second, because printed pieces are surrounded by free, unused powder, no support structures are needed for the metal blasting process. Both advantages reduce the need for post-processing. Additionally, compared to 3D printers based on SLM 3D printing or DED technologies, binder jetting devices are more affordable. They don't need pricey lasers or electron beams, which is one reason. Metal Injection Molding (MIM) powder can also be used with more modern machines. Compared to metal powders created especially for 3D printing, which are often generated in small quantities using pricey production techniques like gas atomization, these are far less expensive. Therefore, producers can further lower the operational expenses for this technology by switching to MIM powder. Binder jetting can print extremely accurate pieces with mechanical qualities similar to those of conventionally manufactured metal parts while also using less expensive raw materials. Finally, compared to other metal 3D printing techniques, metal binder jetting often has a faster build speed.
The latest developments in metal tie spraying
Metal tie spraying enters a new era in the 2010s. Several businesses, ranging from start-ups to major players, are actively working to push the limits of what is currently feasible with this AM technology.
ExOne keeps on innovating. One of the industry's oldest payers is ExOne. ExOne has produced four metal binder systems during the course of its existence, each one improving on the one before it. For instance, the business unveiled the Innovent Plus in 2018, ushering in a new generation of ExOne machines. The device offers two new crucial characteristics even if it is slower than ExOne's prior M-Flex 3D printer:
It has an ultrasonic coater that improves powder flowability and makes material changeover easier. According to ExOne, this revolutionary powder dispensing technology is the most cutting-edge on the market.
Four screen options are included with the recoater to improve material compatibility. Another crucial purpose of this feature is that it allows the machine to process regular MIM powder. Other metal powder 3D printers need carefully formulated powders to operate consistently, especially those that employ a laser or electron beam. Such powders, however, are frequently far more expensive than the components used in conventional metalworking processes. ExOne can provide cost savings and increased material flexibility to customers of its machines by supporting MIM powders with the Innovent+. The business is constantly coming up with new ideas, and it has now integrated the Innovent+'s technology into the high-volume X1 25PRO 3D printer. The device, which was introduced in June 2019, has a sizable build space of 400 x 250 x 250 mm and can print up to 10 different materials.
The company hopes to use this method to make it possible to produce industrial metal components with enhanced surfaces, tight tolerances, and high resolution.
Automation of Metal Binder Jetting
Another business that has distinguished itself in the advancement of metal binder jetting is Digital Metal, a division of a major producer of metal powder under the Höganäs Group. Since its establishment in 2012, Digital Metal has provided their metal binder shot blasting technique as a service.
The DM P2500 3D printer by Digital Metal was introduced in 2017 and is designed for mass producing small, intricate pieces. A 0.042 mm thick layer of metal powder is spread by the machine. Then, in accordance with the part geometry, a binder is expelled. This method is said to be accurate and consistent, making it possible to create parts that are exceedingly small but have a resolution of 35 microns.
Following the sintering procedure, an average surface roughness of Ra 6.0 microns is produced, which is enough for many features and end-use parts such internal channels.
According to Digital Metal, over 300,000 components for a variety of industries, including aircraft, luxury products, dental equipment, and industrial equipment, have already been created using metal 3D printers. Digital Metal introduced a fully automated production model last year in an effort to advance its technologies. This idea proposes that the majority of process phases, including B. build boxes are fed into the printer and then taken out to be processed. The goal is to eliminate all manual labour to enable large-scale, continuous production.
The development of this no-hand production line by Digital Metal represents a significant advancement in the company's metal binder jetting technology.
HP Metal Jet: Making 3D printing a cost-effective production option
After introducing Multi Jet Fusion technology for polymer parts in 2016, HP added the metal-jetting 3D printing system as the next development to its additive offering. Binder jetting technique powers the new metal 3D printer. But HP's technology has a special advantage thanks to its cutting-edge printhead and ink technologies. Despite the inherent speed of binder jetting technique, HP has used its expertise in printhead technology to make it even faster. There are 6 print heads in the Metal Jet system, each with 5,280 nozzles. These numerous rows of nozzles boost the printer's productivity and dependability. HP has also created a cutting-edge binder to speed up and reduce the cost of the sintering process thanks to its expertise in ink technology.
"With metal injection moulding, a binder burnout often requires more than 10% of the component weight. According to Tim Weber, global head of metals at HP, "in our situation, we have less than 1%, a substantial order of magnitude less, making sintering faster, cheaper, and easier. A metal 3D printer that attempts to attain economies and efficiencies comparable to conventional production technologies is the outcome of these developments taken together. HP has not yet started marketing the device. Instead, in order to make the 3D printer commercially available in 2020, the company has started a parts manufacturing service. The mass production of additively built parts could be the sustainable value proposition for metal 3D printing at scale, according to HP's assertions regarding metal jetting.
3DEO: Combination of binder jetting and milling
The method used to create the Intelligent Layering® technology from 3DEO
To make metal 3D printing competitive with conventional production processes, numerous businesses are working hard. 3DEO is one such business that was established in 2016 with the goal of facilitating mass production using metal binder jetting. The business fully redesigned the procedure to accomplish this. The 3DEO machines employ a specialised spray mechanism to evenly distribute the binder over the entire layer rather than using inkjet to selectively deposit the binder.
A hard, thin layer of metal powder is the ultimate result, which is then machined using micro end mills. For each layer, the part shape is carved out using CNC technology. This innovation, called "Intelligent Layering," is the first hybrid system that combines binder jetting and CNC milling. With this combination, 3DEO is able to create small metal parts with an after-sintering density of over 99.5% with extreme precision.
Currently, the only way to access 3DEO's Intelligent Layering technology is through their production service. While maintaining a very flexible platform, 3DEO maintains high quality printed parts by reserving the technology for its own production service.
With a recent order for 28,000 pieces, 3DEO is now working on some of the biggest orders in the metal 3D printing sector.
The increasing production volume serves to demonstrate the technical capabilities of binder jetting to create production parts that are comparable to components made in a conventional manner, even though the company has no ambitions to market its machines.
Desktop Metal: Print metal parts at a remarkable speed
In 2015, Boston-based firm Desktop Metal was established with the goal of delivering on the promise of 3D printing for manufacturing. The business has created an incredibly quick production mechanism to do this.
Single Pass Jetting (SPJ), a quicker variation of the standard binder jetting procedure, is the name given by the business to the technology underlying the metal 3D printer.
The printer will include two full-width printheads and an innovative powder distribution system that can quickly and efficiently distribute powder and binder over the build area.
This bi-directional technology allows for high-resolution printing at up to 12,000 cm3/h, which equates to over 60 kg of metal components per hour with a build volume of 750 x 330 x 250 mm. It is perfect for high-volume manufacture of intricate metal parts because its pace is orders of magnitude faster than that of other metal 3D printers currently on the market.
The production system is also the first binder system with an industrial inert environment that provides solvent recovery and gas recycling for reactive metal printing that is safe. This makes it possible to print a greater variety of metals, including aluminium.
By significantly increasing speed, Desktop Metal's production technology has increased the advantages of metal binder jetting.
It will take some time before Desktop Metal's claims about its production speed can be confirmed because the company has just put its machine available for purchase. The fastest currently marketed binder jetting 3D printer will be used as the production system in this instance.
Among the Metall-3D-Druck technologies, the spraying of metal binders will become one of the most important key technologies. This is made possible by the unique ability to create highly precise components and achieve high press speeds.
The compatibility with well-known and reasonably priced MIM-Pulvern is another crucial development for the success of metalbindemer lasers.
A number of businesses have recognised the metalbindemittelstrahlen's potential for innovation and are actively working to take advantage of the opportunities that are presented. These businesses plan to develop the Metal Binder Jetting in the future. In the end, this technology will let one obtain a valuable share of the entire manufacturing market.
Exzellenc is the leading manufacturer of SLM/DMLS 3D printing service, we offer high performance metal part for our worldwide customers with our deep know-how about metal additive manufacturing. For more details about metal AM please contact our experts.