Advancement of the high temperature oxidation properties of Austempered Ductile Iron with the high performance diffusion coatings
Tech Area / Field
- MAT-ALL/High Performance Metals and Alloys/Materials
3 Approved without Funding
Georgian Technical University, Georgia, Tbilisi
- New Mexico Institute of Mining and Technology / Mechanical Engineering Department, USA, NM, Socorro\nUniversite de La Rochelle, France, La Rochelle
Project summaryAdvancement of the high temperature oxidation properties of Austempered Ductile Iron (ADI) materials will be carried out with the application of high performance diffusion coatings obtained by slurry method. The deposition of single component Al and double component Al+Ni and Al+Cr coatings will be applied on the substrates with various thermal pre-treatment. High temperature experiments will be performed after coating experiments were successfully done and the results will be comparatively studied. As an outcome of the extensive experimental work a novel substrate-coating system will be developed for the potential future application at the elevated temperatures in various application fields: chemical and petrochemical industry, power generation systems working on fossil or renewable energy sources or other engines.
The objectives of the project are:
1) Introduction and advancement of the high temperature oxidation properties of new Austempered Ductile Iron (ADI and its Deformable version DADI) material with the high performance Al, Ni+Al and Cr+Al diffusion coatings by slurry;
2) Development of the slurry deposition technology and determination of optimal parameters of the process with multi- and inter-disciplinary approach;
3) Study of the microstructural characteristics of the deposited layers, developed diffusion coatings as well as the surface peculiarities of their oxidized surfaces after exposure at the elevated (650, 700 and 750OC) temperatures;
4) Scientifically substantiated determination of the processes taking place on the surfaces of substrates when slurries are applied as well as the oxide layers formation mechanisms for all three coatings on ADIs with different thermal pre-treatments, thus giving us privilege of possibility to governing their high temperature properties;
Taking into account the abovementioned, the aim of the project will be a generation of a new knowledge, experience, understanding and scientifically substantiated sequence of the procedures for the successfully reproducible, uniform and high performance diffusion intermetallic coatings on the surface of Austempered Ductile Iron class materials, with deep awareness on the mechanism the oxide scale obeys while it develops on the surface of coated with certain and most optimal parameters/amount of Al as well as co-deposited Al+Cr and Al+Ni;
Current status: up to now some preliminary studies have been performed on DADI and its aluminized (with only 15mg/cm2 amount) surface through high temperature oxidation experiments which have shown tremendous impact of aluminization process on the high temperature features of the material. Those preliminary studies were the strong motivation and encouragement for preparation of the proposed project which will allow us to go even further and obtain even more valuable scientific results useful for the application in the fields listed above.
Scope of activities: Within the proposed project the following general scopes of the activities are planned to be fulfilled: purchasing of the equipments and materials needed for the project; Installation of the new equipment and getting ready for the experiments, detailed and precise planning; Experiments for the obtaining the slutty coatings (determination of optimal parameters); High temperature short and long tests; Structural analysis of pre high temperature exposure and post exposure specimens; Comparison of the coatings from the high temperature prospective; Systematization of obtained results; Publications and conferences; Reports and management. There will be 7 main tasks to be fulfilled which are interdependent and interconnected and there are totally 16 corresponding milestones to accomplish, which directly contribute to the outcome and success of the project and its aim mentioned above.
Role of Foreign Collaborators/Partners: there will be two foreign collaborators to this project. Both of them will be actively involved in project implementation, with different degree of involvement depending on the task. The collaborators are highly qualified and adequately trained professionals from European and American academic institutions: 1) Full Professor in Chemistry of Materials at University of La Rochelle (France), Fernando Pedraza Diaz; 2) Associated professor of mechanical engineering at the New Mexico Institute of Mining and Technology (NM, USA), Sayavur Bakhtiyarov with the expertise in materials science including high temperature materials and other functional materials. GTU group will be tightly and actively collaborating with those researchers through exchanging specimens by mail or in person when meeting at the scientific events or by the visits to their affiliation institutions; exchanging the results and information on the investigated coatings and substrate-coating system; they will be reviewing the reports when needed; there will be conducted frequent communications between GTU team and collaborators, especially when their consultation will be necessary; joint seminars and meetings will be performed through the electronic media or in person (case when GTU team representative will be visiting Prof. Pedraza in ULR or Prof. Bakhtiyarov in NMT);