Mechanical Properties

stiffness

force required to produce elastic deformation

strength

yield stress at onset of plastic deformation; maximum strength at peak load before fracture

hardness

extent of depth of indenter into the surface under an applied load

ductility

measure of the maximum strain before fracture

toughness

measures resistance to fracture

strain

normalized relative deformation

applied stress (uniaxial tension or compression)

load normalized by area

elasticity

reversible

plasticity

permanent

viscoelasticity

rate-dependent or temperature deformation

fracture

mutual competition between intrinsic damage processes and extrinsic crack-tip shielding mechanisms

intrinsic toughening

inhibit damage mechanisms such as cracking or debonding

extrinsic toughening

mechanisms such as crack deflection and bridging act on the wake of the crack