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Composites - overview . Artificial combination of matrix phase & dispersed phase . Matrix: metal, alloy ceramic mat'l polymer . Dispersed phase: particulate fiber. Works like precipitation hardening. Composites - metal matrix composites (MMCs) . Particulates:
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Composites - overview Artificial combination of matrix phase & dispersed phase Matrix: metal, alloy ceramic mat'l polymer Dispersed phase: particulate fiber
Works like precipitation hardening Composites - metal matrix composites (MMCs) Particulates: ThO2-dispersed Ni (TD Ni) sintered Al powder (SAP) - except strengthening maintained at hi T Improves: strength creep resistance hi T corrosion resistance
Matrix mat'ls Composites - metal matrix composites (MMCs) Fibers: Conts - C, SiC, B, Al2O3 Disconts - C, Al2O3 , SiC whiskers May get rxn betwn phases at hi T
Matrix Composites - ceramic matrix composites (CMCs) Particulates, fibers: SiC, B, Al2O3 , C, SiC & Si3N4 whiskers Improve fracture toughness: slow crack growth deflect crack tips redistribute stresses around crack tips bridge crack tips
Composites - polymer matrix composites (PMCs) Fibers: mainly - glass (GFRPs), carbon (CFRPs), aramid, others - B, SiC, Al2O3
Composites Fibers - variables amount fiber length distribution orientation Fiber orientation can be random aligned intermediate
Composites - polymer matrix composites (PMCs) Fibers: mainly - glass (GFRPs), carbon (CFRPs), aramid, others - B, SiC, Al2O3
Composites - polymer matrix composites (PMCs) Fibers: mainly - glass (GFRPs), carbon (CFRPs), aramid, others - B, SiC, Al2O3
Composites - polymer matrix composites (PMCs) Fibers: mainly - glass (GFRPs), carbon (CFRPs), aramid, others - B, SiC, Al2O3
Composites - polymer matrix composites (PMCs) Fibers: mainly - glass (GFRPs), carbon (CFRPs), aramid, others - B, SiC, Al2O3
Composites - polymer matrix composites (PMCs) Fibers: mainly - glass (GFRPs), carbon (CFRPs), aramid, others - B, SiC, Al2O3
Composites - polymer matrix composites (PMCs) Carbon fibers frequently used as woven fabrics impregnated with an epoxy
Composites - polymer matrix composites (PMCs) Woven carbon fiber fabrics in auto industry - 2006 BMW M6 - roof (unpainted) 'vette Z06 - front fenders, wheel wells, floor Porsche Carrera GT ($440,000) - frame Scion accessories - gear shift knob ($49), fuel-filler door ($39), roof pillar appliqués ($75-189), etc.
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