30 Questions
What design consideration helps to avoid galvanic corrosion?
Insulating different metals from each other
Which type of design is recommended to reduce corrosion?
Simple designs with few corners and edges
What should be considered for the discharge opening of a tank during its design?
It should be inclined to avoid water accumulation after flushing
Why is welding preferred over bolts and rivets in metal connections?
Welding ensures a more cathodic connection
What design feature is recommended for parts of a system expected to corrode quickly?
Designing them for easy replacement
Why should gaps that occur during connections be avoided in design?
Gaps can lead to isolation and must be avoided
What can be done to control the formation of a protective precipitate layer in heating and cooling water?
Reacting oxygen with additives
How can the hardness of water be removed?
Reacting oxygen with additives
Which substances are rendered less harmful by increasing their concentration due to their high oxidizing properties?
HNO3, H2SO4, H3PO4
What is the effect of reducing the concentration of corrosive substances on the corrosion rate?
Decreases the corrosion rate
Which type of inhibitors are effective in anodic regions for steel?
Chromates and benzoate
In what conditions are inhibitors effective on metal surfaces?
Both atmospheric and aqueous medium in wet conditions
What is the purpose of cathodic protection?
Forcing the metal to act as the cathode
What are the common metals used in sacrificial anodes for cathodic protection?
Zinc, Magnesium, and Aluminum-Zinc alloys
Why are sacrificial anodes called 'sacrificial'?
Because they corrode instead of the protected structure
In cathodic protection with sacrificial anodes, what is added to protect the structures?
Metals disposed within anode bed
Which method provides a uniform current distribution along buried pipes?
Cathodic protection with sacrificial anodes
Why is Magnesium a commonly used metal for sacrificial anodes?
It has low potential and provides high current
What type of processes are involved in the corrosion of ceramic materials?
Simple chemical dissolution
Why are ceramic materials frequently utilized?
For their resistance to corrosion
What must refractory ceramics resist in many instances?
High-temperature attack by molten metals, salts, slags, and glasses
In what way do ceramic materials outperform metals in harsh environments?
By corroding less at high temperatures and pressure
What distinguishes degradation of polymeric materials from corrosion?
Degradation and corrosion processes are dissimilar
Why are polymeric materials said to experience degradation rather than corrosion?
To emphasize the difference in underlying processes
What is the primary effect of anodic inhibitors on the surface?
They passivate the surface
What happens when there is less than enough presence of anodic inhibitors in the environment?
Corrosion is accelerated
How do cathodic inhibitors function?
They precipitate on the cathode regions
What are some examples of cathodic inhibitors?
Both a and b
What are mixed inhibitors?
They are organic based
How do mixed inhibitors show their effects?
By adsorption
Learn about the resistance of ceramic materials to corrosion, which generally involves simple chemical dissolution as compared to metals. Explore the importance of ceramic materials in various applications due to their corrosion resistance.
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