Key Terms Flashcards
Instrument Calibration History Reports
Reports that normally contain information on
how frequently each instrument is to be or has been calibrated
Coatings Specification
A formal, structured document containing information on a project
(such as scope, terms, schedule, inspection, etc.)
Materials Safety Data Sheets (MSDS):
A form containing data of known substances in a
particular product
Quality Assurance (QA):
Any systematic process that checks whether a product or service
being developed is meeting specified requirements.
Quality Control (QC):
A procedure intended to ensure that a manufactured product or per-
formed service meets the requirements of the client or customer.
Quality Control Technician:
The inspector’s role, primarily responsible for observing and
reporting the technical aspects of a coating project and its conformance or deviation from the
project specification.
Standards:
A term applied to codes, specifications, recommended practices, procedures, classifications, test methods, and guides that provide interchangeability and compatibility. Standards enhance quality, safety, and economy; they are published by a standards-developing organization or group
Anode:
The electrode of an electrochemical cell at which oxidation occurs. Electrons flow away from the anode in the external circuit. Corrosion usually occurs and metal ions enter the solution at the anode.
Cathode:
The electrode of an electrochemical cell at which reduction is the principal reaction.
Electrons flow towards the cathode in the external circuit
Cathodic Protection:
A technique to reduce the corrosion of a metal surface by making that
surface the cathode of an electrochemical cell.
Corrosion:
The deterioration of a material, usually a metal, that results from a reaction with
its environment.
Corrosion Inhibitor:
A chemical substance or combination of substances that, when present in the environment, prevents or reduces corrosion
Crevice Corrosion:
Localized corrosion of a metal surface at, or immediately adjacent to, an area that is shielded from full exposure to the environment because of close proximity of the metal to the surface of another material
Electrolyte:
A chemical substance containing ions that migrate in an electric field
Galvanic Series:
A list of metals and alloys arranged according to their corrosion potentials in a given environment
Generalized Corrosion:
Corrosion that is distributed more or less uniformly over the surface
of a material
Localized Corrosion:
This occurs at discrete sites on the metal surface
Mill Scale:
The oxide layer formed during hot fabrication or heat treatment of metals
Passivation:
A reduction of the anodic reaction rate of an electrode involved in corrosion
Pitting Corrosion:
Localized corrosion of a metal surface that is confined to a small area and takes the form of cavities called pits.
Return Path (Metallic Pathway):
This connects the anode and cathode, allowing passage of
electrons, generated at the anode, to the cathode
Dew Point:
The temperature at which moisture will begin to form on a steel surface
Infrared Thermometers
Devices that measure temperature, using blackbody radiation emit-
ted from objects
Magnetic Surface Contact Thermometer:
One of the most common instruments used to
determine substrate temperature
Psychrometric Chart:
A graph of the physical properties of moist air at a constant pressure
(often equated to an elevation relative to sea level)
Psychrometric Tables:
Booklet used to determine the relative humidity and dew-point
temperature of the air
Relative Humidity:
The ratio, expressed as a percentage, of the amount of water vapor present in a given volume of air at a given temperature to the amount required to saturate the air at that temperature
Repeatability:
The ability of the instrument to give the same readings under similar ambient and target conditions
Sling Psychrometer:
The type of psychrometer most used in coating inspection. It is used to
measure the ambient air temperature to calculate dew point and relative humidity
Wind Speed Monitor:
An instrument to help decide if conditions are appropriate for coating
application projects
Metalizing:
Protective coating - Metals and alloys deposited on steel substrates in a liquid state
Galvanizing:
Protective coating - Steel components dipped into a molten zinc bath to form a metallic coating
Powder Coating:
A protective coating
Many of the chemistries discussed in this course can be for-
mulated as solids. After electrodeposition, they are heated to a molten state for curing
Additives:
Components of a coating, typically added in small amounts to perform a specific function
Adhesion:
The process in which dissimilar molecules cling together due to attractive forces. Adhesion can be chemical, mechanical, polar, or a combination of all three
Barrier Coatings:
A coating that:
(1) has a high resistance to permeation of liquids and/or
gases, or
(2) is applied over a previously coated surface to prevent damage to the underlying coating during subsequent handling.
Binder:
The nonvolatile (won’t evaporate) portion of the vehicle of a formulated coating material
Inhibitive Pigment:
A pigment that passivates (less active to environment)
the metal surface by forming a thin, tightly adherent film or by reinforcing and plugging defects in the natural air-formed film
Inorganic Coatings:
Coatings whose binders are made from non-living things, most com-
monly based on either silicone or zinc
Organic Coatings:
Coatings whose binders are made from living or once-living things
Pigment:
The fine solid particles added during the manufacture of a coating which are substantially insoluble in the vehicle, used to impart color, corrosion control, or decorative properties
Sacrificial Coatings:
Coatings that use a metal that is anodic to steel and corrodes preferen-
tially. Essentially, sacrificial coatings provide cathodic protection, especially in the vicinity of film defects
Solvents:
Added to coatings to liquefy the binder and allow for application in a productive manner
List three (3) desirable properties of a coating?
Chemical Resistance Water Resistance Ease of Application Adhesion to Substrate Cohesive Strength Flexibility and Elongatio Impact Resistance Abrasion Resistance Temperature Resistance Dielectric Strength
There 6 broad classifications of a coating are:
Organic Convertible Thermosetting Inorganic Non-Convertible Thermoplastic
What are the three methods by which a coating provides corrosion control?
Barrier
Inhibitive
Sacrificial
What are the three different ways a coating can adhere to the surface?
Chemical
Mechanical
Polar
A combination of all thre
The two broad classification for curing mechanisms are:
Convertible
Non-Convertible
What are the two (2) primary components of a liquid applied coating?
Pigment
Vehicle (Resin or Binder and Solvent)
Acrylic:
A type of resin polymerized from acrylic acid, methacrylic acid, esters of these acids,
or acrylonitrile.
Alkyd:
A type of resin formed by the reaction of polyhydric alcohols and polybasic acids, part of which is derived from saturated or unsaturated oils or fats
