Magnetically assisted slip casting is a manufacturing technique that uses anisotropic stiff

nanoparticle A nanoparticle or ultrafine particle is usually defined as a particle of matter that is between 1 and 100 nanometres (nm) in diameter. The term is sometimes used for larger particles, up to 500 nm, or fibers and tubes that are less than 10 ...

platelets in a

ceramic A ceramic is any of the various hard, brittle, heat-resistant and corrosion-resistant materials made by shaping and then firing an inorganic, nonmetallic material, such as clay, at a high temperature. Common examples are earthenware, porcelain ...

, metal or polymer functional matrix to produce layered objects that can mimic natural objects such as nacre. Each layer of platelets is oriented in a different direction, giving the resulting object greater strength. The inventors claimed that the process is 10x faster than commercial 3D printing. The magnetisation and orientation of the ceramic platelets has been patented.

Technique

The technique involves pouring a suspension of magnetized ceramic micro-plates. Pores in the plaster mold absorb the liquid from the suspension, solidifying the material from the outside in. The particles are subjected to a strong

magnetic field A magnetic field is a vector field that describes the magnetic influence on moving electric charges, electric currents, and magnetic materials. A moving charge in a magnetic field experiences a force perpendicular to its own velocity and to ...

as they solidify that causes them to align in one direction. The field's orientation is changed at regular intervals, moving the plates still in suspension, without disturbing already-solidified plates. By varying the composition of the suspension and the direction of the platelets, a continuous process can produce multiple layers with differing material properties in a single object. The resulting objects can closely imitate their natural models.

Artificial tooth

Researchers produced an artificial tooth whose microstructure mimicked that of a real tooth. The outer layers, corresponding to enamel, were hard and structurally complex. The outer layers contained glass nanoparticles and aluminium oxide plates were aligned perpendicular to the surface. After the outer layers hardened, a second suspension was poured. It contained no glass, and the plates were aligned horizontally to the surface of the tooth. These deeper layers were tougher, resembling

dentine Dentin () (American English) or dentine ( or ) (British English) ( la, substantia eburnea) is a calcified tissue of the body and, along with enamel, cementum, and pulp, is one of the four major components of teeth. It is usually covered by e ...

. The tooth was then cooked at 1,600 degrees to compact and harden the material — a process known as

sintering Clinker nodules produced by sintering Sintering or frittage is the process of compacting and forming a solid mass of material by pressure or heat without melting it to the point of liquefaction. Sintering happens as part of a manufacturing ...

. The last step involved filling remaining pores with a synthetic

monomer In chemistry, a monomer ( ; '' mono-'', "one" + ''-mer'', "part") is a molecule that can react together with other monomer molecules to form a larger polymer chain or three-dimensional network in a process called polymerization. Classification ...

used in

dentistry Dentistry, also known as dental medicine and oral medicine, is the branch of medicine focused on the teeth, gums, and mouth. It consists of the study, diagnosis, prevention, management, and treatment of diseases, disorders, and conditions o ...

, which polymerizes after treatment. Hardness and durability approximated that of both the enamel and dentine of a tooth.

References

{{reflist, 30em 3D printing processes Biomaterials Magnetism Nanoparticles Ceramic engineering

Technique

Artificial tooth

See also

References