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Symposium CB
Progress in Non-conventional and Novel Manufacturing Routes to Ceramics Advisory Board Invited Lectures This symposium will cover recent progress and emerging novel approaches in a selected number of non conventional or novel processing techniques capable of embodying ceramic material with unique properties not achievable or difficult to be achieved with conventional methods and/or provide simplified and/or environmentally benign and energy saving “green” processing routes. Covered will be dense or porous materials, functional nanoparticles*, fibers, thin and thick films, and laminated, composite, graded and hybrid structures that are capable to offer a variety of innovative functions enabling improved electronic, dielectric, magnetic, optical, electrochemical, biomedical and structural applications. Mechanisms and kinetics of processes, new directions and challenges for the design at atomic/molecular scale of complex high performing, micro-, meso- and macro-structures with optimized properties will be enlightened as well as advances on the state-of-the-art computation applied to the design of materials and processing, novel characterization and imaging tools and ongoing and forecast applications. *Contributions dealing with the synthesis of nanopowders for sintering purposes by the classical ceramic route may be more appropriately submitted to Symposium CA- Ceramic Powders: Advances in Synthesis, Processing and Manufacturing Topical Sessions CB-1 Solution-based processing
Solution-based processing is an attractive and rapidly growing area in the field of materials due to the possibility of reducing the costs of producing various high-quality functional nanoparticles, thin films, fibres, bulk and porous and finely structured materials and devices using relatively low temperatures. A very effective control of stoichiometry, microstructure and morphology and an extreme flexibility in terms of materials and end-use architectures are among the several advantages of this technique.
This Session will report on recent progress in the synthesis of solution processed ceramic materials and related composites and hybrids by techniques such as sol-gel, hydrothermal and solvothermal processing, co-precipitation, spin-coating, spray pyrolysis, electrolytic deposition, etc., and on exploiting their functional properties in view of the diverse applications. Suggested session topics:
Recent progress in the understanding of the structure at the nanoscale and in the thermodynamics of the complex organic-inorganic systems from which polymer-derived ceramics take origin, coupled with the availability of refined and novel fabrication techniques, enable a more precise control of the strcture of the resulting materials and their embodying with novel powerful functionalities capable to be exploited in a broad range of applications from e.g. energy and environment to aerospace and health-care.
This session will address recent developments in PDCs such as: advanced polymer-to-ceramics conversion methods, structure control and characterisation, thermodynamic aspects and modelling, novel fabrication processes and PDCs device components. Suggested session topics:
Elecrophoretic forming is a fairly rapid, cost effective and versatile process in which charged particles in a suspension are deposited in the presence of an appropriate electric field on an electrode and consolidate in the form of coatings, bulk components, laminates, composites, functionally graded materials, nanotubes, etc. in a size range from the nanometer to centimeter scale. A comprehensive understanding of colloidal stability, deposition kinetics and consolidation features, and the appropriate selection of the application modes for the electric field are among the priority issues to scale the process to useful novel materials and applications.
Suggested session topics:
CB-4 Microwave processing
In microwave processing the combination of specific features such as volumetric heating, ultra-rapid heating, temperature/time profiles not readily available in conventional processing as well as non thermal microwave effects that enhance mass transport, may result in faster reaction kinetics and densification rates, decreased sintering temperatures, finer and better controlled microstructures, improved physical and mechanical properties. The technique, particularly suited for materials difficult to handle with conventional tools, is being applied to an increasing number of processes and materials paralleling the progress gained in a more fundamental and quantitative understanding of the mechanisms of microwave-materials interactions, in the efficient control of the process and in the advances in production techniques.
Suggested session topics:
CB-5 Spark Plasma and Flash Sintering 5.1 Spark Plasma Sintering (SPS)
Spark Plasma Sintering is a comparatively new technique consisting of directly applied pulsed dc currents and uniaxial pressure to a powdered material in a die with heating rates typically from 100 °C/min up to 1,500 °C/min. The process results in fully dense, fine grained bodies in very short holding time and at considerably lower temperatures (hundreds Celsius degrees) compared to the more conventional sintering and hot pressing techniques.
Owing to its peculiar features, SPS is gaining increased interest for the production of functional nanoceramics from high purity powders, of composites, cermets, coatings, joints and, being SPS a non-equilibrium process, also of materials containing non-equilibrium phases or materials combining different phases that would not normally coexist. Experimental and theoretical contributions are welcome directed to more precisely define the mechanisms underlying SPS and their effective control, to fix optimum experimental design and to deeply understand and predict the performance of a given material system, both during its consolidation and in final use.
In Flash Sintering, a technique very recently refreshed from metals to the field of ceramics, a direct current field applied by a pair of electrodes to a green ceramic specimen results in a nearly instantaneous (few seconds) densification when the field and the temperature exceed threshold values. This has often been observed to be accompanied by a sharp increase in the electrical conductivity. Exceptional high dnsification rates and low densification temperatures may be obtained with significant time and energy saving, that can be further reduced by application of stress.
The underlying fundamental mechanisms of charge transport, chemical diffusion and the pulse nature of Joule heating effective on the transient phenomena active in flash sintering, and how powder grain size and stoichiometry affect the process appear until now scarcely debated and poorly understood Contributions are solicited directed to precisely defining the process control parameters to fully exploit the potential of Flash Sintering of ceramics through a deeper insight of the densification mechanisms, and to identify the range of materials, shapes and functions to which the techniques may successfully be applied.
Comples multifunctional nano structured materials with peculiar and specially designed electrical, magnetic, electro chemical, bioresponsive and structural properties resulting from bio inspired processing routes are stimulating growing research as they involve such diverse areas as molecular recognition and self assembly, self healing, hierarchical patterning, biotemplating and microorganisms-mediated materials synthesis.
Covered by this Session will be topics ranging from the biomolecular- directed growth and microstructure pattern formation of ceramic meso/nanostructures in bulk and thick/thin film, organic-ceramic composites and hybrids, ceramic-metal heterostructures to their embodying with special functionalities for a number of potential applications in, e.g ., high performance light-weight structures, efficient biosensing materials and catalysts, improved biomedical materials with stimuli-adaptive, self-assembly and self-repairing properties and in electronic, optical and photonic devices. Suggested session topics:
CB-7 Solid Freeform Fabrication
Solid Freeform Fabrication (SFF) or Rapid Prototyping (RP) includes a very different range of fabrication techniques in which a solid physical model of the part is made directly from a 3-D Computer-Aided Design (CAD) file so offering a new freedom to shape complex parts without the constraints imposed by forming, machining, or joining. Depending on the specific SFF technique, (multi)layered ceramics, membrane-like ceramic structures, complex shaped bulk ceramics may be fabricated by versatile and cost effective means.
Contributions exploiting advances in SFF techniques and applications are sought on the following subjects:
CB-8 Other non traditional or novel routes
Special Session CB-9 |