overview of functionally graded materials
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This document provides an overview of functionally graded materials (FGMs), highlighting their definition, classification, processing techniques, and various applications across industries such as aerospace and biomaterials. It discusses the advantages of FGMs, including their ability to withstand high thermal gradients and reduce stress concentrations through gradual material transitions. The document concludes by noting ongoing research challenges and the importance of FGMs in engineering.
overview of functionally graded materials
- 1. M.Tech (Machine Design) Department Of Mechanical Engineering Gudlavalleru Engineering College Guided by presented by Mr. P.N.S.Srinivas, M.Tech(PhD) A. Sabiha Khathun Asst.professor M.Tech(16481D1501) FUNCTIONALLY GRADED MATERIALS - AN OVERVIEW
- 2. • Introduction • Definition • Origin of FGM • Classification of FGM • Metals Vs FGM • Special features of FGM • Processing techniques • Applications of FGM • Scope and conclusion Contents
- 3. Introduction Introduction Definition Origin Metals vs. FGM Classification Processing techniques Applications Scope and Conclusion • A new class of composite materials known as functionally graded materials (FGMs) has drawn considerable attention of the scientific community. • FGMs exist in nature like wood, bamboo, etc. Even human bones are also FGM. • The aircraft and aerospace industry and the computer circuit industry make wide use of FGM that can withstand very high thermal gradients. This is normally achieved by using a ceramic layer connected with a metallic layer.
- 4. • Functionally graded materials(FGM) can be obtained by layered mixing of two materials of different mechanical properties with different volume ratio by gradually changing from layer to layer such that the first layer has only a few particles of second phase and the last has maximum volume ratio of the first phase. • In FGMs, the different micro-structural phases have different functions. The overall FGMs attain the multi-structural status from their property gradation. Introduction Definition Origin Metals vs. FGM Classification Processing techniques Applications Scope and conclusion Definition
- 5. FGM Structure Introduction Definition Origin Metals vs. FGM Classification Processing techniques Applications Scope and conclusion
- 6. 70g of A+30g of B 60g of A+ 40g of B 100g of A 20g of A+80g of B 100g of B Material A Material B FGM structure D I E
- 7. Steel and Aluminium FGM
- 8. • Bones have functional grading. • Skin is also graded to provide certain toughness, tactile and elastic qualities as function of skin depth and location on the body. Introduction Definition Origin Metals vs. FGM Classification Processing techniques Applications Scope and conclusion Some naturally occurring FGMs
- 9. •In technical world functionally graded materials were first proposed around 1984 in Japan during a space plane project. • In recent years this concept has become more popular in Europe, particularly in Germany. Introduction Definition Origin Classification Metals vs. FGM Processing techniques Applications Scope and Conclusion Origin of FGM
- 10. • Space shuttle moves at about 28,000km/hr, the orbiter hits air molecules and builds up heat from friction (30000F,or16500C). • The orbiter is covered with ceramic insulating material designed to protect it from this heat. • The joining of ceramics to metals is of great engineering significance for various advanced technologies, including high temperature structural applications. Introduction Definition Origin Classification Metals vs. FGM Processing techniques Applications Scope and Conclusion
- 11. • Large number of engineering components and tools require material performance by varying with location. The body of gear must be tough, whereas its surface must be hard and wear resistant. A knife needs only to be hard at its cutting edge, elsewhere the material must be strong and tough. • Many of most demanding current applications are fall under this category. • Stress concentrations are reduced, if the transition from one material to other is gradual. • The magnitude of thermal stress at the critical locations can be controlled. Why FGM ?
- 12. • FGM provide capabilities for part integration. Several metallic components can be replaced by a single FGM component. • FGM structures provide in-service monitoring or online process monitoring with the help of embedded sensors. • The matrix material binds the fibers together and transfers the load to the fibers. • The matrix isolates the fibers so that individual fibers can act separately. This stops or slows the propagation of a crack. • The matrix provides a good surface finish quality and aids in the production of net-shape or near-net-shape parts. Special features of FGM
- 13. Introduction Definition Origin Metals vs. FGM Classification Processing techniques Applications Scope and conclusion PROPERTY COMPARISON METALS VS FGMS
- 14. Types of gradation Introduction Definition Origin Metals vs. FGM Classification Processing techniques Applications Scope and Conclusion • Chemical composition gradient • Porosity Gradient • Microstructure gradient
- 15. • As the composition of material is varied from one material into the other, it will result in different phases with different chemical compositions. • The different phases that are produced are dependent on the compositional quantity and manufacturing conditions of the reinforcing material. Chemical composition gradient Introduction Definition Origin Metals vs. FGM Classification Processing techniques Applications Scope and Conclusion
- 16. •Functionally the porosity in the material is made to change with the change in the spatial position in the bulk material. •The pore size gradation can be achieved by varying the powder particle sizes that are used at different locations in the bulk material during the gradation process. Porosity gradient Introduction Definition Origin Metals vs. FGM Classification Processing techniques Applications Scope and Conclusion
- 17. •It can be achieved during the solidification process, such that the surface of the material is quenched. •The core of the same material is allowed to cool down slowly, which would help to produce different microstructures from those on the surface of the material to the innermost part. Introduction Definition Origin Metals vs. FGM Classification Processing techniques Applications Scope and Conclusion Microstructure gradient FGM Flow of Liquid metal Flow of Cooling Water
- 18. According to process of manufacturing: Thin FGM and Bulk FGM •Thin FGM: It consists of relatively thin sections or thin surface coating • Bulk FGM: It consists of volume of materials which require more labor intensive processes Process of manufacturing Introduction Definition Origin Metals vs. FGM Classification Processing techniques Applications Scope and Conclusion
- 19. Thin FGM • Vapour Deposition Technique(i.e., CVD,PVD) • Plasma spraying • Self-propagating high temperature synthesis(SHS) • Ion beam assisted deposition(IBAD) Bulk FGM • Powder Metallurgy • Centrifugal Method • Solid Freeform fabrication method Processing techniques Introduction Definition Origin Metals vs. FGM Classification Processing techniques Applications Scope and Conclusion
- 20. • PVD is characterized by a process in which the material goes from a condensed phase to a vapor phase and then back to a thin film condensed phase. Introduction Definition Origin Metals vs. FGM Classification Processing techniques Applications Scope and Conclusion Physical vapor deposition diagram Physical Vapour Deposition(PVD) technique
- 21. Chemical Vapour Deposition(CVD) technique Introduction Definition Origin Metals vs. FGM Classification Processing techniques Applications Scope and Conclusion • Film is formed by chemical reaction between gaseous compounds.
- 22. Introduction Definition Origin Metals vs. FGM Classification Processing techniques Applications Scope and Conclusion SELF PROPAGATAING HIGH TEMP. SYNTHESIS (SFS)
- 23. SHS = combustion + structure formation SELF PROPAGATAING HIGH TEMP. SYNTHESIS (SFS) Introduction Definition Origin Metals vs. FGM Classification Processing techniques Applications Scope and Conclusion
- 24. Powder metallurgy method Introduction Definition Origin Metals vs. FGM Classification Processing techniques Applications Scope and Conclusion
- 25. Centrifugal method Introduction Definition Origin Metals vs. FGM Classification Processing techniques Applications Scope and Conclusion
- 26. • SFF refers to a category of manufacturing process in which parts are built by deposition of one cross sectional layer of material on top of the next. Introduction Definition Origin Metals vs. FGM Classification Processing techniques Applications Scope and Conclusion Solid free form fabrication(SFF)
- 27. Applications of FGL composites
- 28. Aerospace and aeronautics • Advanced aircraft and aerospace engineering • Rocker heat shields • TBC Introduction Definition Origin Metals vs. FGM Classification Processing techniques Applications Scope and Conclusion
- 29. Introduction Definition Origin Metals vs. FGM Classification Processing techniques Applications Scope and Conclusion
- 30. Introduction Definition Origin Metals vs. FGM Classification Processing techniques Applications Scope and Conclusion Many defense applications now rely on unique properties delivered by modern composite materials.
- 31. Power plant • TBC • Heat exchanger Manufacturing • Machine tools • Forming and cutting tools Introduction Definition Origin Metals vs. FGM Classification Processing techniques Applications Scope and Conclusion
- 32. Biomaterials •Artificial bones and teeth Introduction Definition Origin Metals vs. FGM Classification Processing techniques Applications Scope and Conclusion
- 33. Introduction Definition Origin Metals vs. FGM Classification Processing techniques Applications Scope and Conclusion
- 34. • Solid freeform fabrication technique offers a greater advantage for producing FGM, but there are still lots of issues that need to be resolved with this promising technology. • Research focus on variation of gradient material with respect to thermal stress relaxation of the material. • A proper database of gradient material (including material system, parameters, material preparation and performance evaluation) is to be developed. Introduction Definition Origin Composite vs. FGM Classification Processing techniques Applications Scope and Conclusion Recent researches in FGM
- 35. • Functionally graded materials are very important in engineering and other applications but the cost of producing these materials makes it prohibitive in some applications. • Flexibility in manufacturing of FGM. • For creep problems, functionally graded component is better choice for the design. Conclusion