Technical Ceramics Additive Manufacturing
An Overview of Technical Ceramics
Ceramics are broadly defined as any nonmetallic, inorganic solid that remains hard when heated. Ceramics have been made and used by mankind since the dawn of civilization in their earliest forms such as clay pottery. Ceramics may be crystalline, glassy or both crystalline and glassy, and are typically hard, brittle, and heat and corrosion resistant. Engineered ceramics have been developed to optimize particular characteristics of the material for use in specific applications, for example, to increase strength, toughness, heat—or cold—resistance, optical transparency, electrical resistivity (e.g. electrical insulators) or electrical transmissivity (e.g. superconductors), chemical resistance, wear resistance, aesthetic appearance, etc. Such “high performance” engineered ceramics are typically produced by controlling the main mineral ingredients, the purity of the ingredients and the combination and proportions of additives in the raw material powder, as well as controlling the forming process and the sintering process by which the powdered elements are fused together into their final form. These engineered ceramic materials, particularly those developed explicitly for industrial applications, are also commonly referred to as “advanced ceramics” or “technical ceramics” or even “advanced technical ceramics”.
3D Printing / Addictive Manufacturing Processes for Technical Ceramics
There are many different varieties of 3D printing technology platforms that are deployed for the wide variety of materials used for AM. Among these are technologies that utilize stereolithography-based (SLA) or Digital Light Processing (DLP) approaches to manipulate focused energy sources such as lasers to trace the surface of the part design layer-by-layer in a vat of photo-active liquid resin or paste. As each layer is fused by the laser, the vat lowers and a fresh layer of resin or paste is wiped over the fused surface, and the tracing repeats to fuse resin or paste onto the next layer.
Several companies offering ceramic AM technologies have adopted variations of these DLP or SLA-based approaches, with ceramic particles suspended in the vat of liquid resin or paste. A primary advantage of this approach for ceramic AM is the relatively easier pathway for developing resins or pastes with different ceramic materials. Key disadvantages include the relatively small footprint of such printers, limiting their production capacity and making them less suitable for commercial volume production applications. Printing resolution, and dimensional tolerance of the final part produced, is limited by the focal spot size of the laser. Post-processing of these materials typically requires a separate de-binding step, another process disadvantage.
XJet has developed and introduced the novel and revolutionary NanoParticle Jetting™ (NPJ™) additive manufacturing technology for advanced technical ceramics. NPJ™ technology enables the production of advanced technical ceramic parts with the same ease and versatility of inkjet printing without compromising throughput or quality. Technical ceramics parts made on the XJet NPJ™ platform feature unprecedented levels of detail, finish, accuracy, and precision. With XJet NPJ™, virtually any design with intricate internal details and ultra-fine features that are not attainable with molding, machining or other legacy technical ceramics manufacturing approaches may be realized. This makes XJet NPJ™ a superior approach for many advanced technical ceramics applications. Read more.Technical Ceramics Materials Available for XJet NPJ™ Additive Manufacturing
High Purity Alumina (Al2O3): Alumina is an oxide ceramic (aluminum oxide, Al2O3) material that offers an attractive combination of mechanical and electrical properties that make it an ideal choice for many engineering applications. Alumina maintains its unique mechanical, chemical resistance and electrical insulating properties at very high temperatures and offers superior abrasion resistance. The fracture toughness of alumina actually increases at cryogenic temperatures, making it a good choice for applications requiring performance over a very wide temperature range. Alumina ceramic is commonly available with purities ranging from 85% to 99.99%, and its properties can be fine-tuned for specific applications by addition of other compounds. Marvel Medtech Advanced Manufacturing offers AM of alumina with the highest purity (99.99 %).Material Properties of XJet NPJ™ AM Alumina Ceramic
| Property | Value | Units |
| Density | 3.93 | g/cc |
| Density | >99.5 | % |
| Hardness | 14.5 | GPa |
| Flexural Strength | 450 | MPa |
| Young’s Modulus | 387 | GPa |
| Fracture Toughness | 3.4 | MPa/m |
| Compressive Strength | 2700 | MPa |
| Thermal Conductivity | 32 | W/mK |
| Coefficient of Thermal Expansion | 7.1 @40-400 oC 8.0 @40-800 oC | ppm/oC E-6 |
| Specific Heat Capacity | 0.78 | J/Kg°K |
| Sintering Temperature | 1700 (3100) | °C (°F) |
| Volume Resistivity | 20°C - 1.0E+15 300°C - 2.5E+13 500°C - 5.8E+10 | Ω∙cm |
| Dielectric Strength | 17 | kV/mm |
Zirconia (ZrO2): Zirconia is a type of advanced or technical ceramic material comprising zirconium dioxide (ZrO2) and typically a stabilizing agent. There are three primary types of zirconia ceramic – magnesia partially stabilized zirconia, Yttria partially stabilized zirconia, and fully stabilized zirconia. Zirconia ceramics are known for high mechanical strength and fracture toughness at room temperatures, plus high hardness for wear resistance and thermal and electrical resistivity. Zirconia ceramics are used for making sharp objects like knives, blades, scissors, or parts that require excellent toughness. At Marvel Medtech Advanced Manufacturing, we offer TZ-3Y zirconia ceramic, which is a commonly used industrial formulation of tetragonal zirconia partially stabilized with 3 mole percent Yttria (Y2O3).
Material Properties of TZ-3Y Zirconia Ceramic
| Property | Value | Units |
| Density | 6.02 | g/cc |
| Density | >99.9 | % |
| Hardness | >12.0 | GPa |
| Flexural Strength | 830 – 1050 | MPa |
| Young’s Modulus | 215 | GPa |
| Fracture Toughness | 13 | MPa/m |
| Compressive Strength | 2500 | MPa |
| Thermal Conductivity | 3 | W/mK |
| Coefficient of Thermal Expansion (x10-6/oK) | 10 @40-400 oC 11 @40-800 oC | ppm/oC E-6 |
| Specific Heat Capacity | 0.46 | J/Kg°K |
| Sintering Temperature | 1450 (2640) | °C (°F) |
| Volume Resistivity | 20°C - 1.5E+12 300°C – 8.3E+06 500°C - 8.8E+06 | Ω∙cm |
| Dielectric Strength | 11 | kV/mm |
Partner with Marvel Medtech Advanced Manufacturing for your Advanced Technical Ceramics Additive Manufacturing/ 3D Printing Needs
Our unique expertise in using the XJet NPJ™ technology enables us to handle the most demanding development challenges for advanced technical ceramics. Our ceramics additive manufacturing services / ceramics 3D printing services offering entails working closely with you to understand your application requirements and provide guidance on optimizing part designs for best ceramics additive manufacturing / ceramics 3D printing results. Please visit our Request a Quote for Your Project website page to receive a secure link for uploading your solid model file(s) for our review, or contact us at 1-877-345-6261 or 1-608-688-0868 with your questions on advanced technical ceramics additive manufacturing / ceramics 3D printing.
