Chapter 2 Flashcards
what is an adherend?
A material substrate that is bonded to another material by means of an adhesive
what is adhesion?
A molecular or atomic attraction between two contacting surfaces promoted by the inter- facial force of attraction between the molecules or atoms of two different species; adhesion may occur as chemical adhesion, mechanical adhesion (structural interlocking), or a combination of both
what is adhesive?
Substance that promotes adhesion of one substance or material to another.
what is adhesive bonding?
Process of joining two materials by means of an adhesive agent that solidifies.
what is cohesion?
Force of molecular attraction between molecules or atoms of the same species.
what is contact angle
Angle of intersection between a liquid and a surface of a solid that is measured from the solid surface through the liquid to the liquid/vapor tangent line originating at the terminus of the liquid/solid interface; used as a measure of wettability, whereby no wetting occurs at a contact angle of 180° and complete wetting occurs at an angle of 0°.
what is the diffusion coefficient?
Proportionality constant representing the rate at which a substance is trans- ported through a unit area and a unit thickness under the influence of a unit concentration gradient at a given temperature.
what is the glass transition temperature?
(Tg)—Temperature above which a sharp increase in the thermal expansion coefficient occurs, indicating increased molecular mobility
what is heat of vaporization?
Thermal energy required to convert a solid to a vapor.
what is latent heat of fusion?
Thermal energy required to convert a solid to a liquid
what is melting temp/melting point?
Equilibrium temperature at which heating of a pure metal, compound, or eutectic alloy produces a change from a solid to a liquid.
what is a metallic bond?
Primary bond between metal atoms.
what is micromechanical bonding?
Mechanical adhesion associated with bonding of an adhesive to a
roughened adherend surface.
what is self-diffusion?
Thermally driven transfer of an atom to an adjacent lattice site in a crystal composed of the same atomic species.
what is stress concentration?
State of elevated stress in a solid caused by surface or internal defects or by marked changes in contour.