stress & strain

Question 1

external force acting to deform the material, measures the INTENSITY of the force

Answer 1

stress

Question 2

magnitude of deformation as a result of the applied stress/loading, measure of DEGREE of DEFORMATION

Answer 2

strain

Question 3

when deformation is ____ it can still return, but if it is ___, the deformation is permanent and leads to failure

Answer 3

elastic

plastic

Question 4

three other qualities represented by each curve on a stress/strain graph

Answer 4

strength
ductility
toughness

Question 5

the maximum stress a tissue can withstand without permanent deformation

Answer 5

strength

Question 6

__ strength is the stress AT the yield point of a material beyond which, PERMANENT deformation will occur

Answer 6

yield

Question 7

___ strength is the max stress that a material can WITHSTAND PRIOR to the INITIATION of failure

Answer 7

ultimate

Question 8

___ strength is the stress at which the material actually breaks or ruptures

Answer 8

failure

Question 9

force per unit area req to deform material, represented by stress/strain curve slope STEEPNESS

Answer 9

ductility

Question 10

___ tissues fail at low stress but withstand a large strain, shown by a SHALLOW slope

Answer 10

ductile

Question 11

__ tissues can withstand high stress but fail with relatively low strain, shown with a STEEP slope

Answer 11

brittle

Question 12

the total ENERGY req to cause material failure, which is estimated by the total area under the stress/strain curve

Answer 12

toughness

Question 13

structure with high strength, low ductility, low toughness

Answer 13

bone

Question 14

structure with moderate strength and ductility, high toughness

Answer 14

tendon

Question 15

structure with low strength, high ductility, moderate toughness

Answer 15

ligament

Question 16

ability to return to orig shape when load is removed

Answer 16

elasticity

Question 17

point at which the applied stress can lead to PERM deform

Answer 17

yield point

Question 18

the nonlinear response of the material after the yield point, some degree of deform will persist after removal of stress

Answer 18

plastic region

Question 19

• property of materials to resist loads that produce SHEAR or TENSILE forces
• stretch of this type refers to putt-like behavior

Answer 19

viscosity

Question 20

____ materials are affected by both the rate of loading and the length of time that its subjected to a constant load

Answer 20

viscoelastic

Question 21

three time dependent loading characteristics that viscoelastic structures will show

Answer 21

creep
hysteresis
relaxation