mechanical/rheological properties

study of the flow of matter in liquid ad soft solids

-velocity at which a liquid moved was proportional to the force applied to it

a spring deformed proportionally to the force applied to it

materials with the highest viscous portion

-have elastic portions
-flow and exhibit a certain level of stiffness

- the inner structure of these materals stick together
- tries to retain the materials original form

show the same level of stiffness as long as their structure is not destroyed.

mostly non-newtonian liquid which cause additional complications

-internal friction of a fluid
-tendency to resist flow

an ideal fluid in which the relationship between shear stress and shear rate is a straight line passing through the origin

- relationship between the shear stress and shear rate is non-linear

-true viscous flow
-shear rate is directly proportional to the shear stress

- a fluid with high viscosity

-fluid with low viscosity

-minimum shear stress known as the ‘yield stress’ must be exceeded before flow begins.
-often found in foods
-no flow occurs at low stress

-increasing shear force gives a more than proportional increase in shear rate,

-associated with an increase in volume of the fluid as flow occurs, and it only
occurs in high concentration suspensions

-relative displacement of points within a body
-vector quantity

-unit change due to force
-nondimensional quantity

-tensile strain
-compressive strain
-shear strain

-compression in one plane

- compresses the product in all three dimensions

-occurs when a force is applied laterally

-deformation is homogenous
-material returns to its original shape

shear stress/ shear strain

shear stress is directly proportional to the shear strain

- the ability of an object or material to resume its normal shape after being compressed or stretched

-immediate deformation when the weight is placed on the biological materia

intensity of a point in a body of the internal forces or components of forces that act on a given plane through the point;

-stress at a point calculated on the net cross section by simple elastic theory

stress component perpendicular to a plane on which the forces act

normal stress due to forces directed away from the plane on which they act

normal stress due to forces directed toward the plane on which they act.

The stress component tangential to the plane on which the forces act

The shear stress on a transverse cross section resulting from a twisting action

The maximum or minimum value of the normal stress at a point in a plane

The true normal stress on the minimum cross-sectional area at the beginning of the fracture

-maximum shear stress which a material is capable of sustaining
- based on the original dimension of the cross section

- maximum tensile stress which a material is capable of sustaining

- maximum compressive stress which a material is capable of sustaining

greatest stress which a material is capable of sustaining without any deviation from proportionality of stress to strain

-first stress in a material

- increase in deformation with a decrease or no change in force
- indication of initial cell rupture
- may occur at any point beyond LL

-rupture occur in the early portion of the curve

-rupture occur after considerable plastic flow at such point as R

the capacity of a material for taking elastic or recoverable deformation

- the capacity of a material for taking plastic or permanent deformation
- the unrecoverable part can be taken as a measur of plastic deformation

-greatest stress which a material is capable of sustaining without any permanent strain

- ratio of stress to corresponding strain below the proportional limit

-slope of the curve at the ORIGIN

slope of the curve at any specified stress or strain

slope of the secant drawn from the origin to any point on the curve

- slope of the chord drawn between any two specified points

-strain remaining after complete release of the load producing deformation

aka rigidity

-resistance to applied force

- stress corresponding to the rupture point

stress corresponding to the bioyield point

-area under the curve
- work req'd to cause rupture in the material

- an object under balanced set of forces

- capacity of a materials for storage of strain energy in the elastic range
- area under the curve up to the point LL

-energy absorbed by a materil in a cycle of loading and unloading

ratio of the transverse (lateral) strain to the corresponding axial (longitudinal) strain

- object subjected to a change or size as result of application of balanced set of forces