Zack LyBenjamin HanelerCorrosion on Mechanical Properties IntroductionCorrosion can take place on many different materials, ranging from metal, one of the most common materials to corrode, to some ceramics and polymers. Corrosion is generally an electrochemical reaction that occurs and causes the material to degrade as it reacts with its environment. When this reaction takes place, the metal gives up electrons, which contributes to the rust and oxidation formed on the metal. Corrosion usually occurs because most materials are man-made and therefore unstable and tend to try to return to their original state. As an example, you can imagine an uncoated steel plate hanging outside. Over time, the steel plate will begin to corrode due to its reaction with the oxygen in its environment. If you take that same steel plate and add water into the mix, it will corrode at a more aggressive rate than flat steel because the water allows for more oxygen and iron ion reactions. Now take that same plate and place it in a salt water environment and it will corrode at an even more aggressive rate due to the presence of sodium chloride ions. All metals are susceptible to corrosion, some more than others. It is the material constituting the metal that has a great influence on the corrosiveness of any metal. As mentioned previously, we know that the properties of the material and its environment influence the corrosiveness of any metal. The combination of different metals can also cause corrosion to progress. Scientists have created a chart known as the galvanic series that lists metals and their relative activity in a saltwater environment. This table extends from metals like Platinum, being o...... middle of paper ......d gas, water, electricity and communications services. The direct cost of corrosion on the various public service sectors is $47.9 billion. The types of corrosion vary in each segment due to its different applications. Transportation is another sector that loses a lot of money due to corrosion. This would include planes, vehicles and trains. The total annual direct loss in this sector is $27.9 billion. We have all seen many rusty cars on the road. Without proper maintenance, the same effect would occur on almost everything. There are many types of corrosion that affect different metals in different ways. Some of these types of corrosion include general attack, localized, galvanic, flow-assisted, intergranular, contact and high temperature corrosion. The type of mechanical changes that occur with different metals vary.