4.1 Flashcards
physical properties
observable characteristics of a material
mechanical properties
indicate how a material behaves under various loads
list physical properties
mass (amount of matter in a material)
weight (relies on gravitational forces as well)
volume
density
hardness (resistance material offers to scratching)
electrical resistivity
list mechanical properties
tensile strength (ability to withstand pulling forces)
compressive strength (abilite to withstand being squashed)
toughness (ab. to resist creaking when receiving sudden shock)
brittle (breaks into sharp shards)
plasticity (avility to be formed into new shape permanently)
elasticity (ab. to bend and return to original shape)
ductility (ability to be extruded into wire etc)
stress
tensile force applied to given area (F/A)
strain
response of material due to stress (change in L/original L)
youngs modulus
measure of stiffness of an elastic material. used to select materials for design context
yield point
B on og graph. material will no longer return to initial shape
necking
netween c and d, going tosard breaking
point d on youngs modulus
failure point
point c on youngs modulus
ultimate tensile sternght
material selection chart
charts used to identify appropriate materials based on desired properties
aesthetic properties
aspects of product that relate to tastem texture, smell, appearance
define smart materials
materials designed to react to externla stimuli. adpat, cjhange properties if needed
list smart materials
pieroelectricity – give off small electrical discharge when deformed
shape memory alloys – goes back to original shape after exposure to heat or electricity
photochromicity – reversible change of color when exposed to light
electro rheostatic – fluids undergo change in viscosity when exposed to electric field
magneto rheostatic – fluids underfo changes in viscosity when exposed to magnetic field
thermoeletricity – electricity produced from heat
