02 Material Structures and Properties Free Online FlashCards

How are processing, structure, and material properties related?

Processing changes a material’s structure, and that structure helps determine its properties and performance.

How do crystalline and amorphous solids differ in atomic order?

Crystalline solids have repeating atomic arrangements; amorphous solids lack long-range order.

What structural features explain common behaviors of metals and alloys?

Metals and alloys have metallic bonding and mobile electrons, so they are often electrically and thermally conductive. Many can also deform plastically before breaking.

What is a common trade-off in ceramics and glasses?

Ceramics and glasses are generally inorganic with ionic or covalent bonding. They often resist heat, wear, and chemical attack, but many are brittle under tension.

Why can a fiber composite behave differently in different directions?

Composite properties depend on their components, arrangement, and interface quality. Fiber composites commonly behave differently along and across the fibers.

What distinguishes isotropic from anisotropic materials?

Isotropic materials have similar properties in every direction; anisotropic materials have properties that depend on direction.

How are tensile stress and strain defined?

Stress is force divided by cross-sectional area, while strain is length change divided by original length: $\text{stress}=\frac{F}{A}$, $\text{strain}=\frac{\Delta L}{L_0}$.

What does Young’s modulus measure, and what does it not measure?

Young’s modulus is the slope of the initial elastic region of a tensile stress–strain curve. It measures stiffness, not strength.

What does ductility describe?

Ductility describes how much plastic deformation a material undergoes before fracture.

What does toughness measure?

Toughness describes the energy a material absorbs before fracture.

How do fatigue and creep differ?

Fatigue is failure under repeated loading; creep is slow deformation under sustained load at elevated temperature.

What does thermal conductivity describe?

Thermal conductivity measures how readily heat flows through a material. Metals commonly conduct heat well; many polymers and porous ceramics are useful insulators.