National Institute of Technology, Rourkela Role of Composites for gradual improvement of Aircraft Structure Presented By: Ajit Behera Roll no- 210MM1248 Presented By: Ajit Behera Roll no- 210MM1248

 Background  Why composite preferable for Aero-structure ?  Use of Major Composite in Boeing Airplanes  Different stresses acting on an aircraft  Decline of Cost/weight by Composite  Conclusions  References National Institute of Technology, Rourkela

 Later, the first planes were built with combined construction of wood, fabric, steel and small amounts of aluminum for reinforcement. Manufactures used ash and spruce for the wings which were usually built around two I-shaped spars, and braced either by internal cables or by forming the leading-edge surface with ply. National Institute of Technology, Rourkela  Until the 1930’s, wood was the primary material used in aircraft construction. It was plentiful and cheap, had large bulk and strength for its weight, and could easily be worked into any desired shape.  After World War-I, builders made the transition for the biplane configuration to monoplanes. Among the many structural improvements of this time were the monocoque fuselage and better metals.  Seamstresses applied to covering the wings with linen, cotton, or sometimes silk. In this way demand of composite gradually increased….

 Weight reduction  Challenge in cost reduction  Reduces / Eliminates corrosion  Increases in fracture toughness  Lightning protection  Improvements in fatigue resistance  damage tolerance limit increases  Structural integrity (To carry the damage part load without harming other parts and operation). National Institute of Technology, Rourkela

Fiber glass composite Carbon fiber+Fiber glass composite Stress Strain

National Institute of Technology, Rourkela At Different Time in Year

National Institute of Technology, Rourkela

(E) BENDING (THE COMBINATION STRESS)

National Institute of Technology, Rourkela  Inter-laminar Failure / Delamination / Disbond  Stress concentration such as hole, fillet, also deteriorate strength. It needs additional thickness= weight  Bolted joint is also a weak point on composite structure  Impact Damage strength regression

 Bolted joints  Doors and windows  System provisions (penetrations and attachments)  Access and drain holes  Attachment tabs  Stringer terminations (run-outs)  Bonded attachments National Institute of Technology, Rourkela

 Reduction in fuel Cost- Composite contributes light weight than that of bulk metal and Light weight structure contributes low fuel consumption.  Maintenance cost- Maintenance cost decreases due to less Body ideal time (Repairing time), increase in Change interval of Corroded parts & fractured parts, guarantee for longer inspection interval etc. National Institute of Technology, Rourkela For Boeing787

National Institute of Technology, Rourkela

The application of composite indicates optimal set of minimum structural weight and manufacturing cost. However, exposed aircraft surfaces made from composite materials can prevent problems with respect to its hostile surrounding atmosphere. Many investigations have been going on for evolution of new composite material for future aero-craft structure.

National Institute of Technology, Rourkela [1]Yin Hailian, Yu Xiongqing, Integration of Manufacturing Cost into Structural Optimization ofComposite Wings, Vol. 23, Issue 6, 2010, [2] Hui Juan Feng, Jian Zhang, Xiang Kai Liu, Applied Mechanics and materials, Vol , , [3] Ronald F. Gibson, Principles of Composite Material Mechanics, 3 rd edition, crc-press, Taylor & Francis Group, 53-87, [4] book review, Glare: History of the development of a new aerocraft Material, [5] Joosung Joseph Lee, Historical and Future Trends in Aircraft Performance, Cost, and Emissions, at the Massachusetts Institute of Technology September [6] Alex B. Harman, Chun H. Wang, Improved design methods for scarf repairs to highly strained composite aircraft structure, Vol. 75, Issue 1-4, , [7] Soderquist, J., "Design/Certification Considerations in Civil Composite Aircraft Structure," SAE Technical Paper , 1987, doi: / [8] R. Kaye, M. Heller, Finite element-based three-dimensional stress analysis of composite bonded repairs to metallic aircraft structure, Vol. 26, Issue 4, , 2006.

National Institute of Technology, Rourkela Thank you for your attention.