In chemistry and manufacturing, electrolysis is a method of using direct current (DC) to drive involuntary chemical reactions. Electrolysis is commercially important as a stage in the separation of elements from natural sources such as ores using electrolytic cells.
Electrolysis involves passing direct current through an ionic species that melts or dissolves in a suitable solvent, causing a chemical reaction at the electrodes and material separation.
Electrolysis causes corrosion of dissimilar metals when passed through a DC potential current. This is stray current or circuitry that does not follow the intended path. It can be caused by the following issues:
Improper wiring
Improper choice of building materials
defective appliances
The incoming current will flow through the path of least resistance. Therefore, electrolysis is much more destructive to ships than galvanic corrosion.
Electrolysis is a term loosely applied to corrosion processes. The term refers to a "solution phenomenon" rather than corrosion itself. Electrolysis is the degradation of electrolytes that occurs due to the passage of electrical current through the electrolyte.
In fact, electrolysis is the process of deteriorating metals through a reactive process. Although the result is the same, corrosion and electrolysis differ in how long the process takes and what usually causes it.
The main ingredients needed to achieve electrolysis are:
Electrolyte: A substance that contains free ions
Direct current (DC) power supply: Provides the energy needed to create or release ions in the electrolyte
Two electrodes: one electrical conductor
There are two ways to protect materials from electrolysis:
Repeated replacement of the sacrificial anode
Locate the source of the stray voltage and eliminate it
Saltwater is a more serious breeding ground for marine corrosion because the salt makes it more conductive. However, polluted freshwater can be more conductive with the right pollutants.
Corrosion and electrolysis can wreak havoc on metals in marine environments. A sacrificial anode will help protect the material. However, it is not possible to protect all forms of electrolysis, and protection can be compromised if the anodes are not checked regularly. Constantly replacing anodes becomes expensive as damage can occur before the anode is replaced.
