Instructor: Prof. Yasser Gowayed

Knowledge based problemsFibrous composites

Used with permission

Lecture outline

1. Definition of composite materials2. Types of composite materials3. Fibrous composites4. Textile composites

Definition

Composite materials are made by mixing two or more distinct materials, having a macroscopically

recognizable interface

Types of Composite Materials

Type of inclusion spheres, rods, fibers, flakes

Type of material- Polymer Matrix Composites (PMC)- Ceramic Matrix Composites (CMC)- Metal Matrix Composites (MMC)

Fibrous Composites

Fibers: strong and flexible

Matrix: rigid and inert

Laminated Composites

Textile Composite (3D XYZ woven)

Fibrous Composites

Common industry practice to use angles to name layers: 0, 45, -45, 90

Laminates with similar number of like orientations share similar properties

Naming convention:(0/45/90/90/-45/-0)(0/45/90)s

Terminology – naming conventionfor laminated composites

Balanced laminate implies that for every + orientedlayer there exists a - oriented layer of the same material

(45,0,90,-45,0,90) balanced, un-symmetric(45,0,90,-45,90,0,45) unbalanced, symmetric(10,0,45,-45,-10,30,-30) balanced, un-symmetric(45,-45,0,90,0,-45,45) balanced, symmetric

Terminology – balance and symmetery

The density of any composite is the product of the density of its constituents relative to their volume fraction

c= Vf * f + Vm* m

Vf + Vm = 1

c = composite densityf = fiber densitym = matrix density

Vf = volume fraction of fibersVm = volume fraction of matrix

The rule of mixtures

Composite manufacturing – Compression molding

Fiber/matrix layers

Composite manufacturing - Vacuum bagging

Altitude: 220 n.m. (nominal)Inclination: 51.6 degrees

Dimension: 290 ft (L) x 356 ft (W)

Weight:: 940,000 lbPressurized Volume: 43,000ft3

Power: 110 kW (total); 45kW (users)

International Space Station

FinalConfiguratio

n2004

Textile CMC Turbine Engines

Enabling Propulsion Materials (EPM)CMC Combustor - Lifing & Sub-element Tests

NASA Glenn, Pratt &Whitney and GE