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A great teacher never strives to explain his vision. He simply invites you to stand beside him and see for yourself. – R. Inman. Composites. Fibers - variables amount fiber length distribution orientation. Composites. Composites. Fibers - variables amount fiber length
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A great teacher never strives to explain his vision. He simply invites you to stand beside him and see for yourself. – R. Inman
Composites Fibers - variables amount fiber length distribution orientation
Composites Fibers - variables amount fiber length distribution orientation Fiber orientation can be random aligned intermediate
Materials selection - some considerations Economics Environmental Political Market Aesthetics Material properties
Materials selection - material cost Relative cost - compared to that of hot rolled ASTM A36 plate (0.29C-1Mn-0.28Si) (unit wt. basis)
when drawing SS to rod need lubricant Materials selection - environmental Health hazards Recycling Metals particularly suited to recycling - can be easily sorted, remelted, & shaped Ceramics usually not recycled - many polymers are Composites difficult to recycle - difficult to separate fibers from matrix
Materials selection - political Who writes the specs for contract bids? Will they specify stainless steel rebar in roads & bridges?
vs …… Materials selection - market Carrera GT vs …… Kia
500 MPa P=50 Materials selection - properties
500 MPa Materials selection - properties
Assignment: Review today's classnotes a. fiber characteristics & behavior b. selection considerations c. use of Ashby charts Read pp. 144-151
A great many people think they are thinking when they are merely rearranging their prejudices. (William James) Composites - polymer matrix composites (PMCs) Role of matrix in FR composites: a. transfer stresses betwn fibers b. provide barrier to environment c. protect fibers Slow crack growth deflect crack tips redistribute stresses around crack tips bridge crack tips