TERMS Flashcards
are caused by the direct
contact of one body with the surface of another.
Surface forces
is developed when one body
exerts a force on another body without direct physical contact between the bodies.
body force
All cross sections are the
same throughout its length.
Prismatic
has the same physical and mechanical properties
throughout its volume.
Homogeneous material
has these same properties in all directions.
Isotropic material
reflect the probability that the total loading R will occur for all the events stated.
Load Factors
are determined from the probability of material failure as it relates to the material’s quality and the consistency of its strength.
Resistance factors
If we select two line segments that are originally perpendicular to one
another, then the change in angle that occurs between them is referred to as
shear strain
A slight increase in stress
above the elastic limit will result in a breakdown of the material and cause it to deform permanently. This behavior
is called yielding.
Yielding
The stress that causes yielding is called
yield stress or yield point
the deformation that occurs is
called
plastic deformation
When yielding has ended, an increase in load can be
supported by the specimen, resulting in a curve that rises continuously but becomes flatter until it reaches a
maximum stress referred to as the ultimate stress.
Strain Hardening
Up to the ultimate stress, as
the specimen elongates, its cross-sectional area will decrease.
Necking
Any material that can be subjected to large strains
before it fractures is called a ductile material.
Ductile Materials
Materials that exhibit little or no yielding before failure are referred to as brittle materials.
Brittle Materials
As a material is deformed by an
external load, the load will do
external work, which in turn will be stored in the material as internal energy. This energy is related to the strains in the material, and so it is referred to as
strain energy
When the stress reaches the proportional limit, the strain-energy density is referred to as
the modulus of resilience.
Modulus of Resilience
This quantity represents the entire area under the stress–strain diagram, and therefore it
indicates the maximum amount of strain-energy the material can absorb just before it fractures.
Modulus of Toughness
The ratio of modulus of toughness to the modulus of resilience
Ductility Factor
When a material has to support
a load for a very long period of time, it may continue to deform until a sudden fracture occurs or its usefulness is impaired.
Creep
