Multi-material Ceramic-Based Components – Additive Manufacturing of Black-and-white Zirconia Components by Thermoplastic 3D-Printing (CerAM - T3DP)

Abstract

To combine the benefits of Additive Manufacturing (AM) with the benefits of Functionally Graded Materials (FGM) to ceramic-based 4D components (three dimensions for the geometry and one degree of freedom concerning the material properties at each position) the Thermoplastic 3D-Printing (CerAM -T3DP) was developed. It is a direct AM technology which allows the AM of multi-material components. To demonstrate the advantages of this technology black-and-white zirconia components were additively manufactured and co-sintered defect-free.Two different pairs of black and white zirconia powders were used to prepare different thermoplastic suspensions. Appropriate dispensing parameters were investigated to manufacture single-material test components and adjusted for the additive manufacturing of multi-color zirconia components. Video LinkThe video component of this article can be found at https://www.jove.com/video/57538/ 14,15,16,17 . CerAM -T3DP is based on the selective deposition of single droplets of particle filled thermoplastic suspensions. By utilizing multiple dosing systems, different thermoplastic suspensions can be deposited beside each other layer by layer to produce bulk material as well as property gradients within the additively manufactured green components 18 . Unlike indirect AM processes, in which previously deposited materials solidify selectively over the entire layer, the CerAM -T3DP process does not require the additional effort of removing any non-solidified material prior to the deposition of the next material, making it more suitable for the AM of multi-material components.Although utilizing the CerAM -T3DP process allows the AM of FGM and the realization of ceramic-based components with unprecedented properties, there are challenges to overcome regarding the necessary thermal treatment after the AM process, in order to obtain a multimaterial composite. In particular, the paired powders in the composite material need to be successfully co-sintered, for which the sintering of the components has to be performed at the same temperature and atmosphere. Therefore, it is a prerequisite for all materials to have a comparable sintering temperature and behavior (starting temperature of sintering, shrinkage behavior). In order to avoid critical mechanical stress during cooling, the coefficient of thermal expansion of all materials has to be approximately equal 11 . The combination of materials with different properties in one component opens the door to components with unprecedented properties for manifold applications. E.g. stainless steel-zirconia composites can be used as cutting tools, wear resistant components, energy, and fuel cell Journal of Visualized Experiments

Additive Manufacturing of Functionally Graded Ceramic Materials by Stereolithography

“…Different manufacturing approaches and materials lead to a variety of product properties, such as size, roughness, or mechanical properties. All additive manufacturing techniques can be classified into two groups: direct additive manufacturing technologies 5 , which are based on the selective deposition of the material (e.g., material jetting processes like Direct Inkjet Printing or Thermoplastic 3-D Printing [T3DP]) 7,8,9,10 , and indirect additive manufacturing technologies, which are based on the selective consolidation of the material which is deposited on the whole layer (e.g., ceramic stereolithography [SLA]).…”

Putting Stiffness where it’s needed: Optimizing the Mechanical Response of Multi-Material Structures

“…Prominent among these are additive manufacturing (AM) techniques, many of which are directly suited to select local material compositions, while others can be adapted to at least modify local compositions and thus properties [1][2][3]. In general, examples of either kind exist for arbitrary matrix material classes (polymers [4], metals [5], ceramics [6]). Beyond AM, more conventional manufacturing techniques like metal casting can be employed to generate multi-material structures via approaches like compound or hybrid casting [7,8], the latter transgressing the boundaries of material classes by combining metals and plastics by reversing the processing sequence already known from overmolding [9].…”

Alternative Process Routes to Manufacture Porous Ceramics—Opportunities and Challenges

“…The portfolio of processible materials is nearly unlimited, which could be demonstrated for alumina, zirconia [ 26 ], and cemented carbide [ 28 ]. Furthermore, the suitability for AM of ceramic-based multimaterial and multiproperty components could be demonstrated, e.g., for combinations of stainless steel and zirconia [ 29 , 30 ], white, and black zirconia [ 31 ], as well as the combination of dense and porous zirconia in one AM component [ 32 ].…”