Manufacturing and Processing of Advanced Ceramic Materials: New Advances in Ceramic Processing II: Conventional vs. Additive Manufacturing
Program Organizers: Bai Cui, University of Nebraska Lincoln; James Hemrick, Oak Ridge National Laboratory; Mike Alexander, Allied Mineral Products; Eric Faierson, Iowa State University; Keith DeCarlo, Blasch Precision Ceramics
Tuesday 8:00 AM
October 11, 2022
Room: 411
Location: David L. Lawrence Convention Center
Session Chair: William Carty, Alfred University; Jian Luo, University of California, San Diego
8:00 AM Invited
A Comprehensive Approach to Ceramic Forming Processes: William Carty1; 1Alfred University
Ceramic processing is the foundation of all ceramic manufacturing processes and processing defects are the strength limiting flaws that restrict component performance. For slip casting, the suspension rheology is controlled by five factors: particle-particle interactions, particle concentration, particle size and distribution, particle morphology, and the rheology of the suspension medium. Tape casting appears be a suspension forming technique, but it actually fits more closely with extrusion and vibratory casting, where there are now three factors: water content is now a response dictated by particle packing and the rheology is controlled by the amount of excess liquid in the system. Particle packing is dictated by particle-particle interactions, particle size and distribution, and particle morphology. If the packing efficiency increases the water content necessary for the forming process decreases. Conversely, increasing packing efficiency decreases the water demand. Process windows for tape casting, extrusion, and vibratory casting are defined using Specific Volume Diagrams.
8:30 AM Invited
A Novel Approach to Estimate the Hamaker Constant of Ceramic Systems: Keith DeCarlo1; 1Blasch Precision Ceramics
The Hamaker constant is utilized by ceramic engineers to determine suspension stability and control the microstructure of the final ceramic product; however, calculation of the Hamaker constant is not trivial due to the need to understand the permittivity of each material (particles and medium) as a function of frequency. Therefore, calculation of the Hamaker constant has only been completed for extensively studied systems (e.g. alumina and water). Newly developed ceramic materials do not have the required data to calculate the Hamaker constant and previous methods of estimating the Hamaker constant have yielded poor results. A new method of estimating the Hamaker constant of any ceramic particle in water using only the dielectric constant, refractive index, bandgap, and FTIR data has been developed that correlates well with the exact Hamaker constant calculation allowing for control of the ceramic processing and, subsequently, the final product microstructure of newly developed ceramic materials.
9:00 AM
Impact of Embossing Geometry on the Replication Accuracy of Microchannels in Tape Cast Ceramics: Harrison Teutschbein1; Mingwei Xu1; Yue Qiu1; Chirag Kharangate1; James McGuffin-Cawley1; Jennifer Carter1; 1Case Western Reserve University
The advancement of high-powered electronics requires new thermal-management systems. Active cooling using microfluidics within ceramic substrates can increase device performance over passive radiative fins - if issues surrounding manufacturability can be solved. One approach is to emboss and laminate high thermal-conductivity ceramic tapes to create the necessary embedded micro-scale channels. In this work, we attempt to understand the relationship between load and displacement acquired during embossing to the resulting feature dimensions. Embossing tools with rectangular channels of various channel/wall size ratios (3:1, 1:1, and 1:3) were created to understand how silicon nitride and alumina tapes behave under different constraints. The microchannel and wall features were measured using optical profilometry after embossing, and again after sintering; preliminary results indicate that sintering shrinkage depends on the geometric constraint. These results were used to more efficiently design tooling and loading conditions to meet device design requirements.
9:20 AM Invited
Open Platform Material Development for Additive UV Polymer Manufacturing: Greg Pugh1; 1Tethon
Tethon 3D is a material development company that specializes in highly filled polymers for UV additive manufacturing. Greg Pugh will go over Tethon 3D's open resin and hardware platform approach to custom resin development. Tethon uses their Genesis Base resins to develop countless materials based on a simple logic. This lecture will go over how to leverage the Genesis line of products to develop your own custom filled / ceramic UV resin. We will also discuss some common development problems and solutions.
9:50 AM Break
10:10 AM Invited
Ceramic Binder Jetting Additive Manufacturing: Chao Ma1; Zhijian Pei1; 1Texas A&M University
This talk covers our recent research conducted at Texas A&M University on ceramic binder jetting additive manufacturing. First, a brief literature review is given. Then, our research results are presented to reveal the relationships among various densities, including apparent density, tap density, powder bed density, and green density. Next, our efforts in developing various feedstock powders are discussed, including granulated powder, multimodal powder, and coated powder. Afterward, our research results on the effects of process parameters are summarized, including ultrasonic hopper dispensing parameters, dosing ratio, layer thickness, roller rotation and traverse speeds during spreading, and printing orientation. Furthermore, our work on powder bed compaction is highlighted. Lastly, our research on infiltration as a post-processing method is discussed.
10:40 AM
Multi-Material 3D Printing of Ceramics: Process Overview and Successful Trial Examples: Shawn Allan1; Martin Schwentenwein2; Sebastian Geier2; Nicole Ross1; Nicholas Voellm1; Ryan Fordham1; 1Lithoz America, LLC; 2Lithoz GmbH
Many applications of interest for 3D printing require the use of more than one material in combination to achieve functionality and improved properties. A multi-material approach to high-resolution lithography-based ceramic manufacturing will be presented. Co-printing of different ceramics or even metals in separate layers of a printed part is possible, as well as spatially-resolved combinations within a single layer. This technique paves the way to achieve complex bi-phasic ceramic components. Successful trials that will be presented here include combinations of alumina with colored alumina; zirconia with colored zirconia; and alumina with molybdenum-alumina cermet. The presentation will cover the actual multi-material 3D printing process with a focus on the results and current challenges in terms of co-sintering different ceramic materials. Initial results show that this technological approach holds great potential to pave the way from classical single material structures to bi-material components, and subsequently multi-material and functionally-graded ceramics.
11:00 AM
Process Capability of Lithography-based Ceramic Manufacturing: Ryan Fordham1; Shawn Allan1; Nicholas Voellm1; Nicole Ross1; 1Lithoz America
Lithography based ceramic manufacturing, an additive manufacturing technique for high performance ceramics has matured over recent years towards mass and serial production. The CeraFab System line of DLP ceramic printers has the ability to form intricate ceramic green bodies and ultimately a dense ceramic part. The process for bringing a demonstration geometry with several critical design features from initial CAD design to final production is shown with measurements and inspections performed by a third party. Machine and process capability was investigated through characterization of critical geometry tolerances, repeatability and reproducibility. Statistical process control methodology was used to track final part quality and quantify the variability in the process.