Upload
mohammad-tawfik
View
2.350
Download
4
Embed Size (px)
DESCRIPTION
Introduction to smart materials and their applications in engineering. How to prepare MR (Magnetrorheological) fluids at home? What are Shape Memory Alloys? What are Piezoelectric materials? #WikiCourses https://wikicourses.wikispaces.com/Topic04+Smart+Materials
Citation preview
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
Smart Materials and their Applications in Engineering
Dr. Mohammad Tawfik
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
Smart Material: What?
• Controlled change in properties– Change in mechanical properties (MR fluids, SMA)– Change in geometry (Piezoelectric, SMA)
• Energy Converters!– Mechanical Electrical (Piezoelectric)– Heat Mechanical (SMA)– Mechanical Heat (Viscoelastic)– Etc…
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
Smart Materials: Why?
• Vibration Damping• Shape Control• Noise Reduction• Vibration/Damage Sensing• Heat Sensing
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
Smart Structures: Classification
Wada, Fanson, and Crawly
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
Magnetorheological Fluids
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
MR Fluids
How do they work?• Externally applied magnetic field
in a direction normal to the fluid flow direction form dipoles in the iron particles
• Magnetic poles start attracting each others to the direction of the field, hence forming chains
• The chains then form a skeleton within the fluid, which gains the fluid controllable yield stress
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
Why MR technology?
Mix them and you are done!
Required Materials to synthesize an MR fluid:
• Lithium grease General purpose oil
Micron-sized iron particles
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
MR Fluids
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
Rabinow and Winslow 1950’s
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
MR Damper Fabrication
Prototype Damper
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
Seat Shock Absorbers
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
Seat Shock Absorbers
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
Shape Memory Alloy
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
Shape Memory Alloy
• Change mechanical properties with the change of temperature
• Regain original shape when heated!
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
Shape Memory Alloys
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
Shape Memory Alloys
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
Application
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
SMA Embedding
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
Other Applications
• Dental Fillings• Artificial Joints• Heat Valves• Eye-glasses!
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
Shape Memory Alloys
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
Shape Memory Alloys
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
Piezoelectric Materials
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
Piezoelectric Material
• Electric Field Mechanical Strain : Actuator• Mechanical Stresses Electrical Potential
Field : Sensor
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
Basic Properties
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
Piezo-Fiber Composites
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
Active/Macro Fiber Composites
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
Energy Harvesters
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
MEMS Power Generation
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
Backpack Power Generator
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
Ionic Polymer Metal CompositeIPMC
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
IPMC
• New Material• Shape is controlled by electric field• Designed on the molecule level (NANO
technology)
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
Slow and Fast!
Smart StructuresMohammad Tawfik
#WikiCoursesHttp://WikiCourses.WikiSpaces.com
Thank you for your attention!