Why is my boat corroded despite using a sacrificial anode?

Galvanic corrosion is the most prominent culprit in the destruction of the parts of your boats that are submerged in water. Corrosion happens because your boat parts are made from different metals. Salt water is an electrically conductive electrolyte. When a less noble metal is connected to the nobler by the salty water, it begins to dissolve very fast, thus ruining your boat parts. Boat makers, therefore, created the magnesium anode, which is placed under the boat and stands in as the less noble metal. When the sacrificial magnesium anode dissolves, your ship is left intact. However, there are cases where the arrangement to break the circuit using a sacrificial anode fails to work and your boat parts get corroded anyway.

When the sacrificial anode has a small surface area

An anode's effectiveness depends on good electrical connection, which is determined by its surface area. As your magnesium anode dissolves, its surface area reduced and so does its efficiency. In case the anode is left to dissolve completely, the next least noble metal will start disintegrating. To avoid this problem, always replace your magnesium anode when it is halfway dissolved to preserve your boat.

When the water is warm or polluted

Warm and polluted water creates stray current corrosion which leads to an acceleration in the rate of dissolution of your sacrificial anode. When this happens, and you are not keen on checking the anodes, your boat parts might start getting eaten away. If you have docked your boat in an area with warm, polluted waters, you are advised to check anodes regularly to prevent this problem.

When you use the wrong type of fasteners

Galvanic corrosion does not only happen in two different boat parts, but it also occurs within the same region, when it is made of an alloy. It is common to find boat accessory sellers selling fasteners made from copper and zinc alloys. However, you should always insist on marine grade fasteners made of metals such as bronze and Monel.

Other important boat maintenance tips to remember include using galvanic isolators for the protection of the boat from dockside power issues and avoiding anodes that cause damage to the environment such as zinc and cadmium. It is also advisable to use magnesium anodes on freshwater boats only because the metal is not able to withstand the rate of corrosion which occurs in brackish and salty water. Finally, regular check up on your anodes will help you know when to replace them and avert disaster.

About Me

Choosing a new business model

We have been in sales for a long time and while our business model has been pretty good, we know that there is a lot more potential for us in sales if we can expand our sales horizons to include some of the newer channels for sales including social media channels and promotional materials. It is interesting to see the different techniques and how well they work at connecting us with different sections of our target market. This blog has some tips on how to look for a new sales model for your business and how to check the effectivemness of different models in trials.