What are the advantages of the metal binder jetting (mbj) process?
The Metal Binder Jetting (MBJ) is an additive metal manufacturing process that, by definition, has all the benefits of 3D printing:
- Freedom of design (complex shapes and geometries, not feasible by conventional means, customization)
- Short deadlines
- Green technologies (energy, material consumption, reduction of stocks, reduction of assemblies, carbon footprint of manufacturing, etc.)
The Metal Binder Jetting is an emerging technology with distinct advantages that make it a process for the future. It differs from other 3D printing technologies by several advantages.
First, Metal Binder Jetting (MBJ) is the most productive metal additive manufacturing process on the market. Today, some MBJ machines are capable of producing up to 7 dm3 of parts per hour, which is about 30 times higher than powder bed laser melting machines.
A wide range of part number and a significant reduction in costs illustrates this productivity. Indeed, the Metal Binder Jetting adapts to the production of 1 to 100,000 pieces per year.
Unlike LBM, the printing phase does not require manufacturing support. This means that the parts can be "stacked" in the build box. There is therefore no need for a specific machining step after the process.
The surface roughness of the as-sintered parts (i.e. without any post-treatment) is approximately 6 m Ra (generally between 4 and 10 µm Ra depending on how the orientations influence the effect of the binder and the "staircase" effect). Other industrial 3D printing technologies generally give rise to surface roughness greater than 10 µm Ra, excluding post-processing. Starting from a good surface condition makes it easier to reach very low roughness levels with post-treatment steps. For example, with a simple sandblasting step it is possible to achieve a surface finish of 2 µm Ra. By combining different post-treatments, it is then possible to obtain mirror-polished surface states.
Unlike LBM, the printing phase does not require manufacturing support. This means that the parts can be "stacked" in the build box. There is therefore no need for a specific machining step after the process.
The MBJ process makes it possible to achieve a precision of the order of ± 0.5% on the dimensional dimensions with a resolution of 35 µm.
This makes it possible to achieve a quality of detail equivalent to or better than other 3D printing technologies.
Metal Binder Jetting technology is based on the powder sintering process. Powder sintering makes it possible to address a very wide range of materials. To date, however, mature materials remain limited.
For example, powder bed laser (LBM) technologies can only address weldable materials.
Sintering makes it possible to obtain a homogeneous microstructure of the materials, which ensures better repeatability in terms of mechanical strength.
By way of comparison, LBM technologies work with weld seams, thus rendering the microstructure inhomogeneous.
IS MBJ metal 3D printing synonymous with eco design and eco production?
Metal 3D printing technology and more specifically MBJ technology offers both eco design and eco production thanks to the following aspects:
The ability to optimize the structure to reduce the amount of material used. (Exemple: lattice structure)
The use of only the necessary amount of material.
Reduced energy consumption because it consumes less energy than other technologies.
Reuse of unbound powder.
Limiting production to what is strictly necessary thanks to its speed of production.
The reduction of production steps and the resulting number of transportations.
Ordering a part from us is a step towards eco-design, the design of tomorrow. For more information, you can download our brochure here .
What are the obstacles of the metal binder jetting (mbj) process?
The Metal Binder Jetting is linked to certain constraints that do not make it accessible to the greatest number and may require complementary to other technologies.
The Metal Binder Jetting is a process comprising several manufacturing steps and requiring several associated equipment (printing machine, mixer, powdering machine / sieving, ovens, sintering furnace, post-processing equipment). The whole system can lead to a significant budgetary investment. Thus, in order to access a process that is both industrial and competitive, the most important item of expenditure is the sintering furnace and its equipment.
Regarding this aspect, the Poral company, whose core business is sintering, was able to access the MBJ while limiting its initial investment.
Note that there is also a human investment to be taken into consideration because to date there are also manual steps which require operating time (management of green parts, depowdering, installation for sintering, layer removal for separation of supports…).
The sintering causes a shrinkage of the part, that is to say a reduction in volume of more than 40%. Controlling this sinter shrinkage is therefore essential to obtain parts with the right dimensions.
On certain types of parts, iterative loop tuning may be necessary to maintain tight tolerances.
Among the 3D printing technologies, one of the strengths of the MBJ is its panel of eligible materials, although at present it still knows its limits. Here you will find the materials available today on the market in MBJ .
To date, the development of materials that can be used in MBJ occupies a central place among machine manufacturers, technical centres and manufacturers who use this technology, such as the PORAL company .
In general, the MBJ is preferably dedicated to parts of limited size because the step of dusting green parts is tricky for those of very large size. The order of magnitude of the majority of parts made in MBJ fit into a cube of 100mm side with a length of up to 250mm.
The MBJ is also limiting for very thin wall thicknesses (less than 0.5mm) or very thick (upper than 3cm).
Certain types of parts have little or no interest in being manufactured in MBJ and other processes will be more appropriate, from a technical or economic point of view, for parts of simple shapes, easily machinable. This also applies to parts with tight tolerances. Although having a very satisfactory resolution and repeatability compared to other 3D printing technologies, the MBJ process will be limited to tolerances of ±0,5%. In some cases, the combination of MBJ and machining can be an optimal solution.
For more information on the constraints of this technology, contact us !
Why choose poral additive metal?
