When an aluminum plate is bolted to a steel...

Question 1 / 2707066636eee28f7522a1c51e50b

Question 1 of 2707066636eee28f7522a1c51e50b

When an aluminum plate is bolted to a steel plate, what is required at the bolted joint to minimize bimetallic corrosion?

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Question 1 of 27070

When an aluminum plate is bolted to a steel plate, what is required at the bolted joint to minimize bimetallic corrosion?

🔍 Key Concepts

• Galvanic (bimetallic) corrosion between dissimilar metals in the presence of an electrolyte (seawater) • The relative position of steel and aluminum in the galvanic (noble) series • Ways to interrupt electrical paths between dissimilar metals at joints

💭 Think About

• Ask yourself: Do we want steel and aluminum to be in good electrical contact, or do we want to prevent electrical current from flowing between them in seawater? • Consider what happens to the less noble (more active) metal when it is directly connected to a more noble metal in a saltwater environment. • Think about common shipbuilding practice: when mounting aluminum fittings on a steel structure, what do shipyards typically insert at the joint to control corrosion?

✅ Before You Answer

• Verify which choice prevents or reduces electrical continuity between the two plates at the joint. • Check which answer mentions non-conductive (insulating) materials rather than increasing metal-to-metal contact. • Eliminate any options that suggest steel and aluminum are so close in the galvanic series that no special measures are needed.

Question 1 of 27070

When an aluminum plate is bolted to a steel plate, what is required at the bolted joint to minimize bimetallic corrosion?

The plates should be bolted together in such a way as to ensure good electrical contact between the plates.

The plates should be electrically insulated from one another by use of non-conductive gaskets and non- conductive ferrule sleeves with the bolts.

Steel and aluminum are so close together on the Noble series that no particular provision need be made for bolting steel and aluminum plates together.

The plates should be bonded together electrically by joining the plates by a bonding strap in addition to bolting together.

Question 1 / 2707066636eee28f7522a1c51e50b

Question 1 of 2707066636eee28f7522a1c51e50b

When an aluminum plate is bolted to a steel plate, what is required at the bolted joint to minimize bimetallic corrosion?

Back

Question 1 of 27070

When an aluminum plate is bolted to a steel plate, what is required at the bolted joint to minimize bimetallic corrosion?