Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
40 Cards in this Set
- Front
- Back
|
Density
|
amount or mass of material in a given volume
|
|
|
Boiling or melting point
|
Temp at which a material boils or melts
|
|
|
Vapor pressure
|
measure of a liquids tendancy to evaporate and become a gas
|
|
|
Thermol Conductivity
|
Rate of heat flow through a material
|
|
|
Heat Capacity
|
a measure of the amount of thermol energy that a material can hold
|
|
|
Specific heat capacity
|
of a material is the amount of energy needed to raise the temperature of 1 unit of mass of that material by 1 C
|
|
|
Heat of fusion
|
amount of energy required to melt a material
|
|
|
Heat of a vaporization
|
amount of energy required to boil a material
|
|
|
dimensional change
|
percentage of the expansion or contraction of a dental material
|
|
|
Coefficent of thermal expansion
|
measure of this change in volume in relation to change in temperature
|
|
|
Percolation
|
process of heating and cooling, and the accompanying of opening and closing of a gap between dental materials and tooth
|
|
|
Electrical Conductivity
|
rate of flow of electricity
not important in dentistry |
|
|
Viscosity
|
a materials ability to flow
|
|
|
Wettability
|
measured by determining the contact angle of a liquid on a solid
|
|
|
Hardness
|
property that is measured by scientific instruments that press a special a tip into the test of material
|
|
|
Durometer
|
used to measure the hardness of impression materials and other elastic polymers
how deep a loaded ball will go sink |
|
|
Abrasion resistance
|
wear resistance of dental restorations to food and substance
|
|
|
Water sorption
|
materials that absorb water
|
|
|
Color
|
a complex phenomenon that is a psycological response to a physical stimulus
|
|
|
Radiolucent
|
not seen on radiograph...refers to areas that appear dark on radiograph
|
|
|
Radiopaque
|
refers to areas that appear light on radiograph
|
|
|
Elasticity
|
spring/rubber band
returns to original shape |
|
|
Stress
|
load inch area
force that developes in a loaded object |
|
|
Modulus of elasticity
|
stress versus strain
|
|
|
plastic deformation
|
sting does not return to original shape ...permenantly strched out
|
|
|
Elastic limit
|
point on stress/strain plot where the line starts to curve and plastic deformation begins
|
|
|
Ultimate strength
|
stress where fracture occurs
|
|
|
Compression
|
pushing or crushing stress
|
|
|
Tension
|
pulling stress
|
|
|
shear
|
(slip) parts of objects slide by one another
|
|
|
Torsion
|
stress is a twisting force
|
|
|
Bending
|
common stress...a combination of different types of stress
|
|
|
Yeild Strength
|
Strong more important than ultimate strength
|
|
|
Resilience
|
an ability to absorb energy and not be deformed
|
|
|
Toughness
|
amount of energy requiired to fracture
|
|
|
Fracture toughness
|
measure of energy required to fracture a material when crack is present
|
|
|
Fatigue
|
how long it takes to fail
|
|
|
Creep
|
small change in slope when an object is under continuous pressure
|
|
|
Stress relaxation
|
slow decrease in force over time
|
|
|
Stress concentration
|
Stress increases around defects
|
