Aeronautical engineering - structural dynamics and aeroelasticity

Presentation A

Presentations

SELF - HEALING MATERIALS Group 15 1 General definition of self -healing materials Healing mechanisms Biomimetics Applications Conclusions 1 2 3 4 5 2 S elf -healing materials are smart materials that can intrinsically repair damage • Longer lifetime • Reduction of inefficiency due to degradation and material failure 1 General definition of self - healing materials 3 Healing efficiency 1 How much does the material retain its physical properties after healing? ������ = ��������������������� ������������� ����������������������� ������������� 4 Classification 1 NON AUTONOMIC ( ������������ > ������ ) : Require external trigger e.g., heat, light, chemicals AUTONOMIC (������������ < ������ ) : Do not require any additional external trigger Damage itself is the stimulus 5 Classification 1 INTRINSIC : No separate healing agents, it is a property of the material itself EXTRINSIC: External healing components intentionally embedded into the matrix SELF -HEALING POLYMERS SELF -HEALING CERAMIC COMPOSITE 2 6 h 1 2 Chemical approaches Physico -chemical approaches Healing mechanisms Physical approaches 7 h 1 Healing mechanisms Physical approaches Interdiffusion Phase separated morphologies Melting interdiffusion Shape -memory recovery 2 Focus on: Interdiffusion 8 h 1 Healing mechanisms Physical approaches Interdiffusion Phase separated morphologies Melting interdiffusion Shape -memory recovery 2 Focus on: Phase separated morphologies https://onlinelibrary.wiley.com/doi/epdf/10.1002/adma.202008052?saml_refe rrer= 9 h 1 Healing mechanisms Physical approaches Interdiffusion Phase separated morphologies Melting interdiffusion Shape -memory recovery 2 Focus on: Melting interdiffusion https://www.tandfonline.com/doi/pdf/10.1179/095066010X12646898728408 10 h 1 Healing mechanisms Physical approaches Interdiffusion Phase separated morphologies Melting interdiffusion Shape -memory recovery 2 Focus on: Shape -memory recovery https://onlinelibrary.wiley.com/doi/epdf/10.1002/adma.202008052?saml_refe rrer= 11 h 1 Healing mechanisms Chemi cal approaches Focus on: Covalent rebonding Reactive chain ends • Covalent rebonding • Free -radical rebonding Supra -molecular chemistry • H -bonding • Guest -host chemistry • Metal -ligand coordination • Ionic interaction 2 12 h 1 Healing mechanisms Chemi cal approaches Focus on: Supra -molecular chemistry Reactive chain ends • Covalent rebonding • Free -radical rebonding Supra -molecular chemistry • H -bonding • Guest -host chemistry • Metal -ligand coordination • Ionic interaction 2 https://onlinelibrary.wiley.com/doi/epdf/10.1002/adma.202008052?saml_refe rrer= 13 h 1 Healing mechanisms Physico -chemical approaches Focus on: Encapsulati on Van der Waals interactions Encapsulation Cardiovascular network 2 14 https://cecas.clemson.edu/urbanresearch/wp - content/uploads/2018/12/Picture1.png 1 Healing mechanisms Physico -chemical approaches Focus on: Van der Waals interactions Van der Waals interactions Encapsulation Cardiovascular network 2 https ://ceca s .cl ems on.edu/urba nres ea rch/wp -content/upl oa ds /2018/12/Picture1.png 15 h 1 Healing mechanisms Physico -chemical approaches Focus on: Cardiovascular network Van der Waals interactions Encapsulation Cardiovascular network 2 https://onlinelibrary.wiley.com/doi/epdf/10.1002/adma.202008052?saml_refe rrer= 16 Biomimetics 2 3 BIOMIMETIC PRODUCT Functional principle Biological concept Technical application Functional principles found in biological model are transferred to technical applications TECHNICAL question Technology pull process BIOLOGICAL question Biology push process Abstraction 17 Biomimetics 3 Wound Inflammatory response Cell proliferation Matrix modelling Damage Actuation: triggering Transport Chemical repair Biological system Synthetic system 18 Biomimetics 3 4 Bone healing Self -Healing concrete 19 Applications 3 4 Protec tive coatings The typical car keyed that you find when your parking is bad Shock absorbing materials Bullet -proof vests for military crew E-skins Placed on prosthetic limbs for self - repair, to work as real skin Space structures Spacecraft structure faces harsh environments Asphalt Cracks due to the cold can be closed 20 Space applications 3 4 5 Causes of space structure degradation : • Temperature fluctuations • Radiations (UV and GCR) • High vacuum • Atomic oxygen • Mechanical vibrations • DEBRIS IMPACT No autonomous repair leads to failure of the system SELF -HEALING MATERIALS → repair damaged structure without human intervention • More reliable systems • Longer missions to Moon and Mars 21 Space applications 3 4 5 Self -healing core shell nanofibers POLYMERS → encapsulation • Carbon -fiber reinforced with resins • Polyvinyl cyanide • Exploit UV radiations to initiate damage repair • High strength and toughness METAL ALLOYS → microcapsule • Titanium alloy • Stainless steel • Electropulsing treatments to heal damage 22 Conclusions 4 5 The usage of self -healing materials • Permits reusability • Wide variety of approaches for different situations • Will increase the space mission duration • Still r equires lots of research 23 Thank you for your attention! 24