Cleaning and Corrosion Control Flashcards
- (1) In the corrosion process, it is the cathodic area or dissimilar cathodic material that corrodes
(2) In the Galvanic or Electro-Chemical Series for metals, the most anodic metals are those that will give up electrons most easily
Regarding the above statements
a. Only No. 1 is true
b. Only No. 2 is true
c. Both No. 1 and No. 2 are true
b.
- A non-electrolytic chemical treatment for aluminum alloys to increase corrosion resistance and paint-bonding qualities is called
a. Anodizing
b. Alodizing
c. Dichromating
b.
- When an anodized surface coating is damaged in service, it can be partially restored by
a. Applying a thin coat of zinc chromate primer
b. Chemical surface treatment
c. Use of a suitable mild cleaner
b.
- Caustic cleaning products used on aluminum structures have the effect of producing
a. Passive oxidation
b. Improved corrosion resistance
c. Corrosion
c.
- The interior surface of sealed structural steel tubing would be best protected against corrosion by which of the following?
a. Charging the tubing with dry nitrogen prior to sealing
b. Evacuating moisture from the tubing before sealing
c. A coating of linseed oil
c.
- What should be done to prevent rapid deterioration when oil or grease comes in contact with a tire?
a. Wipe the tire thoroughly with a dry cloth, and then rinse with clean water
b. Wipe the tire with a dry cloth followed by a wash down and rinse with soap and water
c. Wipe the tire with a cloth dampened with aromatic naphtha and then wipe dry with a clean cloth
b.
- One way of obtaining increased resistance to stress corrosion cracking is by
a. Relieving compressive stresses (via heat treatment) on the metal surface
b. Creating compressive stresses (via shot peening) on the metal surface
c. Producing nonuniform deformation while cold working during the manufacturing process
b.
- Corrosion caused by galvanic action is the result of
a. Excessive anodization
b. Contact between two unlike metals
c. Excessive etching
b.
- How many magnesium engine parts be cleaned?
a. Soak in a 20 percent caustic soda solution
b. Spray with MEK (methyl ethyl ketone)
c. Wash with a commercial solvent, decarbonize, and scrape or grip blast
c.
- Why is it important not to rotate the crankshaft after the corrosion preventive mixture has been put into the cylinders on engines prepared for storage?
a. Fuel may be drawn into one or more cylinders and dilute or wash off the corrosion preventive mixture
b. The seal of corrosion preventive mixture will be broken
c. Engine damage can occur from hydraulic lock
b.
- For which of the following reasons would a water break test be conducted?
a. To make certain that a newly alodized aluminum surface is sufficiently coated
b. To make certain that a bare metal surface is thoroughly clean
c. To make certain that an anodizing coating has been sufficiently removed before an electrical bonding connection be made
b.
- The lifting or flaking of the metal at the surface due to delamination of grain boundaries caused by the pressure of corrosion residual product buildup is called
a. Brinelling
b. Granulation
c. Exfoliation
c.
- Which of the following are acceptable to use when utilizing chemical cleaning agents on aircraft?
(1) Synthetic fiber wiping cloths when using a flammable agent
(2) Cotton fiber wiping cloths when using a flammable agent
(3) Atomizing spray equipment
a. 2 and 3
b. 1
c. 2
a.
- Fretting corrosion is most likely to occur
a. When two surfaces fit tightly together but can move relative to one another
b. Only when two dissimilar metals are in contact
c. When two surfaces fit loosely together and can move relative to one another
a.
- Nickel-cadmium battery cases and drain surfaces which have been affected by electrolyte should be neutralized with a solution
a. Boric acid
b. Sodium bicarbonate
c. Potassium hydroxide
a.