MTE 455 Test 1 Matching

vocab words from hw 1 and 2

Elasticity

A fully-recoverable response; that is, a component is loaded and unloaded without any permanent change to its shape or integrity

Plasticity

Permanent shape change without cracking; deformation is permanent and remains after the load is removed

Failure

When stress has exceeded a critical limit and the material can no longer effectively carry a load

Fatigue

Describes how a material weakens and eventually fails due to repeated stress cycles

Creep

Slow, but constant time-dependent deformation

Fracture

Involves the creation or propagation of a crack that separates a portion of the component from the remainder

True Stress

The force applied to a material divided by the material’s actual cross-sectional area at a given time

True Strain

The most representative value when there is a significant change in the material’s length and cross-sectional area when a force/load is applied; it is more accurate than engineering strain because it accounts for changes in the material’s dimensions during deformation

Engineering Stress

Quantitatively describes the distribution of internal forces within a specimen; the force applied to a material per unit area before it deforms; an approximation of true stress

Engineering Strain

A unitless measure of a material’s ability to deform or change in shape when a force/load is applied due to the distribution of internal forces; an approximation of true strain

Hooke’s Law

Mathematical application of the fact that the force needed to compress or extend a spring by a certain distance is directly proportional to that distance and the stiffness of the spring

Stiffness

The measure of a material’s resistance to deform under an applied force/load

Compliance

The measure of a material’s flexibility when subjected to an external force/load; opposite of stiffness

Isotropy

When properties are the same in all directions

Anisotropy

When properties are directionally dependent

The Poisson Effect

A tensile stress along the z axis causes the material to stretch along the z axis and to contract along the x and y axes

Yield Strength

The critical point at which a material transitions from elastic to plastic deformation regions

Strain Hardening

The process of increasing a material's strength and hardness by testing plastic deformation at temperatures below its recrystallization range.

Ultimate Tensile Strength

The maximum stress a material can withstand before necking and failure

Necking

When there is a significant reduction in cross-section before fracture; typically occurs in ductile materials

Equivalent Stress

A scalar value used to determine whether a material will yield or deform permanently under complex loading

Critical Value

A threshold at which a material’s behavior, state, or structure changes significantly

Principal Stress(es)

The maximum and minimum normal stresses that act on specific planes within a material; where shear stress is zero

Stress Deviator

The portion of the total stress tensor that induces distortion (shape change)

Hydrostatic Stress

Induces volume change while the shape stays the same

Uniaxial, Biaxial, and Triaxial Loading

Determined by the number of orthogonal directions along which stress is applied to the material