Corrosion Flashcards
What manual lists warnings applicable to hazardous materials and structural repair?
NAVAIR 01-1A-509
What are the two types of chemical poisoning?
Acute- one time poisoning when vapors are inhaled in a short time. Chronic- repeated daily exposures for extended periods
Where can you find the authorized chemicals for use on aircraft?
ACMS or the Authorized Chemical List card, marked 00ACL.0.
Who may authorize a one-time purchase of chemicals not on the ACL to meet operational commitments?
Engineering Officers
What is the chemical or electrochemical deterioration of a material or its properties due to a chemical reaction with the surrounding environment?
Corrosion
What are the 4 conditions that MUST exist before metal corrosion occurs?
Presence of an ANODE (metal with high tendency to corrode,) CATHODE (dissimilar conductive material,) and ELECTROLYTE (conductive liquid that connects the anode and cathode,) electrical contact between ANODE and CATHODE (usually in the form of metal-to-metal contact or a fastener.)
Describe uniform surface corrosion.
Results from direct chemical attack on a metal surface and only involves the surface. Generally dulling or etching of the surface, becomes rough and possibly frosted in appearance.
Describe galvanic corrosion.
Occurs when differnt types of metal are in contace with each other and an eletrolyte such as saltwater. Recognized by buildup of corrosion by-product at the joint between metals.
Describe pitting corrosion.
White or gray powdery deposit similar to dust. When deposit is cleaned away, tiny pits or holes can be seen in the surface of the metal
Describe intergranular corrosion.
An attack on the grain boundaries of the metals.
Describe exfoliation corrosion.
Advanced intergranular corrosion where the surface grains of the metal are lifted up by the force of expanding corrosion.
Describe crevice corrosion.
Occurs when the electrolyte has a different concentration form in one area than another.
Describe stress cracking corrosion.
Intergranular or transgranular cracking of a metal caused by the combined effects of constant tensile stress and corrosion.
Describe Fatigue corrosion.
Cracking of metals caused by the combined effects of cyclic stress and corrosion.
Describe Filiform corrosion.
Special form of oxygen concentration cell corrosion or crevice corrosion. Occurs on metal surfaces with an organic coating system. Leave wormlike trace of corrosion products beneath paint.
