Addbor N25

Addnorth is a Swedish manufacturer of filaments for 3D printing, renowned for producing very high quality filaments, as well as for the strong development of materials for applications in science and engineering.

Addbor N25 is a unique material developed in cooperation with the company Additive Composite, based in Uppsala. It is a material composed of a polyamide matrix loaded with 25% by weight of boron carbide (13% by volume).

Boron carbide, or black diamond, has a hardness of 9.3 Mohs, one of the highest and close to the hardness of diamond. However, its hardness is not its most significant property, but it stands out for having the capacity to absorb neutrons without forming long-lived radioisotopes. This makes it one of the most efficient neutron radiation absorbers, and it is frequently used in the anti-radiation shielding of nuclear reactors.

The base of Addbor N25 is formed by a co-polyamide specially formulated to facilitate the 3D printing of the material, as it has a very low shrinkage. This low shrinkage during printing allows to obtain very low dimensional tolerances, as well as high precision. In addition, the use of a polyamide base gives the material excellent mechanical resistance, as well as the ability to work continuously at temperatures above 100ºC.

Image 1: Properties of the Addbor N25. Source: Addnorth

Thanks to this, the Addbor N25 makes it possible to produce complex parts capable not only of absorbing neutron radiation, but also of working under the most demanding conditions.

Table 1: Attenuation factors of Addbor N25 for thermal neutron radiation (V=2200 m/s, λ=1.8 Å) for printed parts with 100% filling.

In addition, in high energy radiation, the plastic matrix can act as a nuclear moderator, reducing the neutron speed and improving the material performance.

For certain applications, it can be useful to incorporate heavy metal elements to protect from the gamma radiation generated, both externally and by the neutron absorption of the material.

Potential applications include the production of protective elements both in research environments and in the nuclear or medical industry, such as camera housings and inspection equipment, diaphragms and blockers for radiation beams in X-ray equipment and synchrotrons, structural components, etc.

For all these reasons, Addbor N25 is a unique 3D printing material, with great potential both in particle physics research and in the nuclear and medical industries.