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Composites - polymer matrix composites (PMCs). Matrix. Composites - polymer matrix composites (PMCs). Very common - polyesters, vinyl esters. Composites. Role of matrix in FR composites: a. transfer stresses betwn fibers b. provide barrier to environment c. protect fibers.
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Composites - polymer matrix composites (PMCs) Very common - polyesters, vinyl esters
Composites Role of matrix in FR composites: a. transfer stresses betwn fibers b. provide barrier to environment c. protect fibers Matrix/fiber bond: matrix must wet fiber physical & chemical bond desirable mechanical interlocking Fibers frequently coated w/ coupling agent
non-coupled coupled Composites
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