High Thermal-Shock Resistant Ceramics
The Technology of Manufacturing of High Thermal-Shock Resistant Ceramics
Tech Area / Field
- MAN-MPS/Manufacturing, Planning, Processing and Control/Manufacturing Technology
3 Approved without Funding
Institute of Electronic Materials, Armenia, Yerevan
- OJSC “М&МАVR”, Armenia, Artashat
- Imperial College of Science, Technology and Medicine, UK, London\nTechnical University Hamburg-Hamburg / Institute of Polymer Composites, Germany, Hamburg\n[Individual specialist]\nUniversity of Missouri-Rolla, USA, MO, Rolla\nUniversity of Science and Technology, Poland, Krakov\nCNRS / Université de Rennes 1, France, Rennes\nInstitut für Fügetechnik und Werkstoffprüfung GmbH, Germany, Jena\nUniversity of North Texas / Department of Materials Science, USA, TX, Denton\nThe State University of New Jersey RUTGERS / Material Science & Engineering, USA, NJ, Piscataway
Project summaryWithin the frame of A-540 project, β-spodumene glassceramics and aluminum titanate with improved qualities as well as high thermal-shock resistant alumina ceramic composition have been developed.
β-spodumene glassceramic(Li2O·Al2O3·4SiO2) is produced by the glasswork technology, with subsequent controlled crystallization. It can be independently used in the manufacture of technical devices or household high heat-resistant and fire-resistant utensils, as well as high-temperature thermal-shock resistant solder-glass materials. From a ceramic processing point of view, it can be used as a rather low-melting additive for decreasing the sintering temperature.
Aluminum titanate (β-Al2TiO5) is produced by a specially developed ceramic technology based on fine-dispersed powders of corundum (α-Al2O3) and rutile (TiO2) with SiO2, Li2O, spodumene and mullite additives. It can be independently used for a heat exchanger and for filtration of discharge gases in thermal units, in particular, gas-turbine engines and generators, engines of internal combustion. As an additive of a ceramic composite, the material is used for decreasing the temperature expansion coefficient (TEC), thus, increasing thermal-shock resistance.
Heat-resistant ceramic compositions are produced by calcining finely-dispersed (0.2-1.0 μm) powders of α-Al2O3, mullite, aluminum titanate, and β-spodumene glassceramics. These compositions will withstand temperatures not less than 1500 ºC, have a density of 3.3-3.6 g/sm3, a TEC value in an interval of 20-700 ºC of (8-26) ·10-7 K-1, a pressure strength of 270 and bending strength of 40 MPa, lgδv at 100 ºC ≈ 13, ε ≈ 8, tgδ ≈ 50·10-4 and, what is especially important, a stability against repeated thermal cycling under conditions of “1400 ºC – flowing water”. The compositions are recommended for use under conditions of sharp temperature swings, in particular, for manufacturing of thermostressed parts for airplanes, spacecraft, rockets, various engines, generators, non-inertial high-temperature electroheating elements of closed-film type, etc.
The present proposal seeks an extension of the ISTC's A-540 Project at the “Development of Technologies” stage and pursues the purpose of development of the above-mentioned project results for industrial implementation.
Accordingly, within the framework of the proposed Project the following will be done:
- Industrial technologies of melting and processing the quenched cullet of the spodumene structure will be developed;
- The equipment and conditions for conducting controlled crystallization of the quenched cullet will be selected to acheive the maximum crystallization of ?-spodumene glassceramic powder;
- The equipment, conditions of synthesis, cooling and dispersion of the aluminum titanate achieve the optimum structure under industrial conditions will be selected, with the purpose of development of a material with the maximum negative value of TEC;
- A technology of stabilizing the aluminum titanate by the optimum additives will be developed, with the purpose of increasing its stability in the most challenging temperature regions;
- The equipment will be selected and industrial technologies of joint additional crushing and milling of initial components will be developed, along with technologies of formation and calcining of the optimum composition. Its basic physical, chemical and operational parameters will be determined;
- Technological requirements and ways of target quality assurance of compositions will be developed;
- Methods, equipment and conditions of formation, as well as calcining, cooling and preliminary processing of products of simple configurations from the optimal composition will be defined;
- Specifications on the above listed materials and technological instructions will be developed, provisional technical and economic calculation of their manufacturability will be carried out.
The Project will result in the following:
- Recommendations on the manufacturing technologies of production of ?-spodumene glassceramic powder, stabilized aluminum titanate and constructional ceramics with the above listed properties, as well as suggestions on manufacturing products of simple configurations of the ceramics developed in this program;
- Specifications on the above mentioned materials, technological instructions and provisional technical and economic calculation on their manufacturability under industrial conditions;
- Pilot lots of β-spodumene glassceramics powder, aluminum titanate, construction ceramics and materials produced for presentation and marketing of the achieved results.
The theoretical importance of the project is determined by enrichment of a database on glassceramics, ceramic and composite materials and the attempt of determining their interrelations.
The economic importance of the project?is determined by the following:
- Achieving a new generation of glass-ceramic, ceramic and composite materials with improved properties and of greater demand, and, consequently, a higher level of profitability in comparison with earlier analogues;?
- An opportunity to replace rather expensive and heavy metal constructional materials by cheap and light ceramic compositions, which are especially economical in applications of space- and aircraft production;
- An opportunity to expand the sphere of application of new generation materials, in particular, in manufacturing of high-temperature solder-glass materials, protective coats and facing refractory slabs of various applications.
Extension of the project at the “Demonstration of technology” stage and introduction of the achieved results for batch production may be carried out after some interested organizations and enterprises, who suggest specific programs, have been identified. Participation of the representatives of the Leading Research Institute in these works is guaranteed.
The project fully conforms to the goals and objectives of ISTC in terms of its content and project developing staff.
The theme of the Project lies within the scope of scientific interests and opportunities of both the Leading Research Institute and the Participant Institute. The author of the proposal, as well as many of the potential project developers from both institutes, possess a long-term work experience on development and application of perse composite materials in batch production. They also have taken an active part in development of A-540 Project which represented the initial stage of the problem as mentioned in the introduction of the present proposal. All the above -mentioned allows us to expect a positive outcome of the present proposal in case of its financing.
The International Science and Technology Center (ISTC) is an intergovernmental organization connecting scientists from Kazakhstan, Armenia, Tajikistan, Kyrgyzstan, and Georgia with their peers and research organizations in the EU, Japan, Republic of Korea, Norway and the United States.
ISTC facilitates international science projects and assists the global scientific and business community to source and engage with CIS and Georgian institutes that develop or possess an excellence of scientific know-how.