Moduluses Flashcards
Stiffness(flexibility)
Ultimate load and elongation
Determined from load displacement curve
Deformation
Change in geometry of body
Stiffness
Slope of load-deformation curve
Flexibility
Slope of deformation-load curve
Ultimate load
Highest load achieved
Max elongation
Deformation at ultimate load
Stress
Normalized internal force
Reaction to external force
Normal force
Changes length
Shear force
Sliding down
Strain
Rate of deformation due to applied stresses
Types of deformation
Length change
Normal strain
Shape change
Shear change
Modulus of elasticity
Slope of elastic region
Young’s modulus of elasticity
Yield strength
Highest stress material can withstand without undergoing significant yielding and permanent deformation
Perfectly plastic zone
Specimen continues elongation with out any increase in stress
Ultimate strength
Stress increases
Known as strain hardening
Stress at end is ultimate stress
Necking
Stress drops
Continues until fracture occurs
Poissons ratio
Related change In length to change in height (height)/(length)
Bulk modulus of elasticity
Change in volume/unit volume
Measure of compressibility
Creep
Viscoelastic property
Tendency of material to deform permanently under constant stress while still under yield strength
Stress relaxation
Viscoelastic property
Observed decrease in stress I. Response to same stress over time
Anisotrophy
Exhibiting different properties with different values when measured in different directions
Heterogeneity
Properties differ by location
Incompressibility
Ability to maintain constant volume
Residual stress
Stress retained even after force is removed
