The world of ceramic additive manufacturing is still evolving, and a handful of industry players have risen to the fore of the niche segment. Among them is 3DCERAM SINTO, a ceramics AM specialist based in Limoges, France, a historic hub for ceramics production. The company, which was founded in 2001, is a pioneer of 3D printed ceramics, having created some the first 3D printed ceramics parts back in 2005. Since then, the company has refined its additive manufacturing technology—specifically its SLA-based CERAMAKER platform—and has developed many types of ceramic materials suitable for AM. The company now offers a complete range of products for ceramic 3D printing in the aerospace, biomedical and defense areas, among others.
As a leading player in the ceramics AM segment, 3DCERAM understands the industry’s landscape and knows better than most about the extraordinary properties of ceramic materials. Typically, technical ceramics are used in applications where all other materials—polymers and metals—have failed.
This is because, though the exact properties depend on the type of ceramic, technical ceramics demonstrate exceptionally high strength and resistances. One of the hurdles to the broader implementation of technical ceramics has been that they are challenging to process. With additive manufacturing, however, processing the materials is becoming easier and more accessible.
Like with all additive manufacturing, one of the key factors in increasing the accessibility and adoption of ceramic AM is in offering a broad portfolio of material options. This is where 3DCERAM has particularly excelled: the company has been developing ceramic 3DMIX slurries for its CERAMAKER technology for nearly 20 years and now offers a diverse range of suspensions for aerospace, biomedical, electronic and foundry core applications.
The company’s success on this front has been driven by its team of expert ceramic engineers, who are developing slurries that are printable and are equal in quality to traditionally manufactured ceramics. The team also pays close attention to the high loading content of its ceramics to reduce shrinkage in final parts.
Finally, many of the materials are tuned to to meet the requirements of various industries. In the aerospace sector, for instance, one of the most critical properties is a low thermal expansion coefficient. In the biomedical segment, on the other hand, biocompatibility is a must. In manufacturing electronics, several material properties come into play, including high thermal conductivity, electrical insulation and ionic conduction.
As of April 2020, 3DCERAM SINTO has a ceramic materials portfolio consisting of the following ten materials:
Alumina is one of the fundamental technical ceramic materials, and it demonstrates a number of beneficial properties, such as good mechanical behavior in high temperatures, good thermal conductivity, electrical resistance, excellent hardness and good wear and chemical resistance. 3DCERAM SINTO’s Alumina material has a purity of 99.8% and is commonly used in the aerospace and biomedical industries. Alumina demonstrates better stiffness and less density compared to titanium alloys and has a similar CTE.
Alumina Silica (Al203-SiO2)
3DCERAM’s aluminum silica material is typically used for the production of cores for Equiax casting. The presence of alumina in the silica material slows down the rate of crystallization and reduces the mechanical resistance of the core.
Biomedical, Dental, Energy
3DCERAM currently offers two grades of zirconia, a material with good temperature and wear resistance, as well as excellent hardness and chemical stability. The first grade, 3% Yttria, is ideal for the production of surgical instrumentation and odontology prosthetics (crowns and bridges) because of its excellent mechanical properties at room temperature and other properties. The second grade of zirconia is 8%Yttria, which is used in fuel cell applications because of its ionic conductivity.
Cordierite is a magnesium alumina silicate with the chemical formula 2MgO.2Al2O3.5SiO2. The aerospace industry is especially interested in this ceramic slurry because of its low thermal conductivity, low expansion coefficient, low dielectric loss and good heat resistance.
Tri Calcium Phosphate (TCP)
Tri Calcium Phosphate (TCP) is a calcium salt of phosphoric acid whose chemical composition is also similar to bone. Unlike HAP, however, TCP is resorbable in vivo. 3DCERAM says TCP and HAP can be used in combination to 3D print parts with improved osseointegration properties.
HAP is a mineral form of calcium apatite with a chemical composition that is similar to bone. Because of its bone-like properties, the material is ideal for biomedical applications and especially the production of osseous substitutes such as skull implants. HAP is a non-resorbable material.
Silicon nitride is a recent addition to the portfolio. The ceramic is one of the hardest and most resistant technical ceramics on the market. It also boasts a number of other properties, including low density, thermal shock resistance, wear resistance, high mechanical properties at elevated temperatures and a low thermal expansion coefficient. The material has applications in the aerospace sector and is particularly well suited to the production of pump and valve components and semiconductors.
Fused Silica (SiO2)
Also known as quartz glass, fused silica is a glass-based material with several sought after properties, like high chemical resistance and thermal resistance, high thermal expansion coefficient and thermal shock resistance, high radiation resistance and good transparency. The material is used for a range of applications, including for the production of crucibles for solar applications and cores in turbine blades. Fused silica can be used in combination with nickel and aluminum complex cores.
Alumina Toughened Zirconia (ATZ)
As the name suggests, ATZ is a material consisting of a combination of alumina and zirconia, the latter of which has the highest mechanical resistance at room temperature of any technical ceramic. By mixing both technical ceramics, the fracture resistance of the material is improved. The biocompatible ceramic material is well suited for biomedical applications like orthopedic prosthetics, as well as industrial applications.
Aluminum Nitride (AIN)
One of 3DCERAM SINTO’s newest materials is aluminum nitride (AIN), a ceramic material that boasts excellent thermal conductivity and electrical insulation properties. The material, which also has high mechanical properties across the board, was developed for use in the electronics industry and is well suited for producing parts such as heat sinks.
Part of 3DCERAM SINTO’s mission is to continually develop new slurries for ceramic 3D printing. The company approaches this on several fronts. For one, it works independently to development ceramic materials for its portfolio (as seen here). Second, it works closely with customers, including universities and ceramic manufacturers to adapt their qualified ceramic materials for AM.
The company has even established an on-demand formulation service which enables customers to adopt ceramic 3D printing while using materials based on ceramic powders that have already been qualified for a specific application. In line with this, the CERAMAKER platform is an open system, which means that customers can also develop materials and printing parameters in-house.
Having a greater offering of materials for printing ceramics is a vital part of sustaining the growth of technical ceramic 3D printing more broadly. Because of this, the company continues to invest in the development of new and cutting-edge ceramic AM materials.
This article first appeared on 3dpbm’s AM Focus 2020 Materials eBook