When Raise3D first announced its MetalFuse solution for end-to-end metal fused filament fabrication in late 2021, it became one of a small number of companies in the AM industry to specialize in metal extrusion technologies. Today, the company’s solution is used for quickly and safely producing all sorts of metal products, from jigs and fixtures, to functional parts and prototypes, to small-batch end-use components. As we’ll see in more detail, Raise3D’s technology really excels when it comes to precision. This is enabled due to a combination of hardware and software optimizations, as well as a deep collaboration with materials developer BASF Forward AM. Let’s take a look at how the company’s Forge1 3D printer and MetalFuse workflow stand out within the metal AM and—even more specifically—metal FFF segments.
What metal FFF brings to the table
In the early days of 3D printing, metal additive manufacturing was dominated by the laser powder bed fusion (LPBF) process. And while this process is still widely used to produce highly complex metal parts at an industrial level, there are now more technology options for metal AM adopters. Among them is metal fused filament fabrication (FFF).
This process functions similarly to polymer FFF, using a heated nozzle to melt and extrude filament, building components on a build plate one layer at a time. The key difference lies in the materials used: metal FFF processes such as Raise3D’s MetalFuse solution, use metal composite filaments like Ultrafuse® 316L, which are made up of a high percentage of metal powder bound in a thermoplastic matrix. The metal FFF process also requires post-processing steps, like debinding and sintering, to transform green parts into dense metal components.
Metal FFF brings certain benefits to the table that other metal AM processes do not. For one, the technology is safer to use than technologies that use loose metal powder as feedstock. Risks like powder inhalation and explosion hazards, which must be considered when using LPBF, are not an issue with metal FFF, and operators therefore do not require the same degree of training or personal protective equipment (PPE) to use the technology. This also makes metal FFF more versatile: it can be used in many environments, from labs and shops to office spaces, providing that ventilation is adequate.
Metal FFF platforms are generally also more accessible in terms of cost. The technology hardware, which does not include high-power lasers, is significantly cheaper than LPBF platforms and even binder jetting systems. Some metal FFF platforms, including Raise3D’s technology, can also be used in combination with existing debinding and sintering machines used in metal injection molding (MIM) workflows. Overall, the relatively new process has an edge in the metal AM sphere, particularly for manufacturers seeking an entry into metal 3D printing with the desire to scale into production.
Addressing the pain points of metal FFF
As with any technology, however, metal FFF has been limited by certain hurdles. Factors like consistent extrusion and perfect first layers have presented challenges that influence the tolerances and overall quality of final metal parts. Standard nozzle sizes, typically measuring 0.4 mm and up, also present limitations in terms of the size of design details that can be achieved as well as surface finish. Finally, while metal FFF comes with less of a learning curve than other metal AM processes, it does still require specialist knowledge of process parameters in order to achieve the best print results.
From another perspective, materials can be seen as a limiting factor. Today, the market for high-quality metal filaments is relatively small when compared to the diversity of laser powder bed fusion materials, which limits the range of applications the technology can be used for. Moreover, the quality of filaments is directly related to the quality of final prints, so it’s important that as more materials come to market, they are of the highest possible quality.
All these pain points were top of mind for Raise3D as it developed its MetalFuse solution, and it has successfully addressed many of these issues through hardware and software features, process optimization and a fruitful materials partnership with BASF Forward AM.
Forge1, a machine optimized for metal FFF
At the core of Raise3D’s MetalFuse solution is its 3D printer, the Forge1. The dual-extrusion machine has been engineered to meet the specific requirements of printing metal filaments and to deliver reliable, high-quality results. As we saw, consistent filament flow has been traditionally difficult to achieve when printing metals, but the Forge1 integrates certain features that ensure filament feeding and extrusion perform to a high standard.
Specifically, the Forge1 has a built-in spool holder that eliminates excessive pulling as the filament is fed into the nozzle. This system ultimately helps to ensure the filament tolerances are maintained and that the material is not deformed as it passes through the extruder gears, which can lead to inconsistent material extrusion and flow. According to Raise3D, the specific height of the spool holder also minimizes the risk of twisting filament as the printhead moves around the build area.
Raise3D has also paid special attention to the Forge1’s build plate in order to ensure the quality of the critical first layers. The machine comes with a “precision glass plate” that is both flatter than standard glass plates (<=0.15mm vs >=0.35mm) and has a lower coefficient of thermal expansion. Paired with the RaiseTouch calibration feature, the Forge1 glass plate promotes better layer adhesion and minimizes warping for more precise parts.
In order to print metal parts with fine details and a smooth surface finish, the Forge1 is also compatible with nozzles as fine as 0.2 mm in diameter. This smaller nozzle capability enables thinner layers, more detail and ultimately higher precision and tolerances for metal components.
Accessible process parameters
In addition to tackling metal FFF limitations on the hardware front, Raise3D has also developed a version of its slicer program dedicated to metal printing, ideaMaker Metal. As the company explains it: “ideaMaker Metal is a modified version of ideaMaker optimized for the use of Ultrafuse® Metal Filaments, with unique features that provide the required part density and repeatability to create end parts of the highest quality.”
The software enables users to successfully 3D print parts without needing extensive process knowledge. In other words, it makes metal FFF accessible to a wider range of adopters. Aspects of metal FFF, like shrinkage in the sintering stage, can easily be calculated and controlled in ideaMaker Metal through its automatic shrinkage plate. Other helpful features include automatic support layer generation and templates for all processes and Ultrafuse materials. The slicer program also supports modifiers for multi-setting printing in the same print job.
Ultimately, the slicer software empowers users to make the most out of the metal AM process and material feedstocks by allowing users to customize all parameters to suit the needs of specific applications.
To address the need for high-quality metal filaments, Raise3D has partnered with BASF Forward AM to develop optimized process parameters for the latter’s Ultrafuse metal filaments. Together, the companies are continually working to improve print outcomes and quality through data-driven parameters.
The largest chemical producer in the world, BASF has an extensive portfolio of metal injection molding feedstocks. These materials, consisting of “metal and ceramic powders compounded with tailor-made binding agents” are available through the Catamold® brand and come in over 30 varieties. By working with additive manufacturing companies such as Raise3D, it is possible for BASF Forward AM to develop each of these Catamold materials into high-quality metal filament.
To date, Raise3D’s Forge1 platform is compatible with three Ultrafuse metal filaments: Ultrafuse® 316L, Ultrafuse® 17-4 and Ultrafuse® Support Layer. Ultrafuse® 316L is a stainless steel composite filament with excellent corrosion resistance; Ultrafuse® 17-4 is a stainless steel filament that can undergo heat treatment to attain greater strength and hardness; and Ultrafuse® Support Layer is a support filament developed to facilitate removal of supports from metal parts post-sintering. (The Forge1’s dual extrusion capability enables the simultaneous printing of both build and support materials.)
It’s worth noting that BASF’s metal filaments are well paired with Raise3D’s dedicated MetalFuse workflow (comprising the Forge1 3D printer, D200-E debinding unit and S200-C sintering station). The D200-E system uses catalytic debinding, in which the green part is exposed to a catalyst, which breaks down the binder, resulting in a brown part. The S200-C then sinters the brown part, resulting in part density up to 97% of wrought iron’s density.
Ultrafuse metal materials are also compatible with other industrial MIM catalyzing and sintering equipment. This means production volumes can be scaled by pairing multiple Forge1 printers with an established MIM post-processing workflow. Post sintering, metal Ultrafuse components comply with MPIF 35-2015 MIM standard, which is relevant for automotive, electronics, medical and consumer goods industries, to name just a handful.
All in all, Raise3D’s Forge1 and broader metal FFF offerings are always being improved to unlock the highest potential of compatible metal materials. As Tobias Rödlmeier, Business Development Manager at BASF Forward AM, puts it: “The best system we could have wished for our customers. An open innovation platform that makes no compromises in accuracy and stability.”
Learn more about metal FFF and specifically about Raise3D’s MetalFuse solution in the company’s recent white paper.