You Spend More on Rust Than Gasoline (Probably)

Summary

This video explores the critical issue of corrosion in infrastructure, using the 1995 Folsom Dam failure as a starting point. It discusses the impact of corrosion on metals, the science behind it, and how it affects everyday structures like bridges and pipelines. Corrosion is a global challenge, costing trillions annually. The video also covers various forms of corrosion, material selection, and protective measures, including passivation and weathering steel. It highlights real-life consequences, like the Flint water crisis, showing why corrosion engineering is essential for safety and efficiency in modern society.

Takeaways

• 😀 Folsom Lake's spillway gate failure in 1995 resulted in a massive loss of water due to corrosion in the gate's pivot mechanism.
• 😀 Corrosion is a significant global issue, costing approximately $2.5 trillion annually, and it impacts various industries, including infrastructure.
• 😀 Corrosion occurs when metals, like steel, are exposed to environmental factors like moisture and oxygen, leading to the formation of oxides (e.g., rust).
• 😀 The corrosion process is electrochemical, requiring an anode, cathode, electrolyte, and a current path to facilitate the reaction.
• 😀 Different types of corrosion can occur, including uniform corrosion, galvanic corrosion, and pitting, and engineers need to be aware of these for effective prevention.
• 😀 Corrosion engineering combines chemistry, material science, and structural engineering to mitigate the detrimental effects of corrosion on infrastructure.
• 😀 Material selection plays a vital role in reducing corrosion; noble metals (e.g., gold, platinum) resist corrosion, while metals like steel are more vulnerable.
• 😀 Passivation is a protective process where certain metals form a stable oxide layer that prevents further corrosion. Examples include stainless steel and aluminum.
• 😀 Weathering steel (Corten Steel) forms a protective rust layer, preventing further corrosion, and is widely used in structural applications like bridges.
• 😀 Corrosion causes massive economic costs, including an estimated $276 billion annually in the U.S. alone, representing over 3% of the GDP.
• 😀 The Flint water crisis (2014) exemplified the severe consequences of mismanaging corrosion in infrastructure, leading to a public health emergency and widespread lawsuits.

Q & A

What caused the Folsom Dam spillway gate to fail in 1995?

The Folsom Dam spillway gate failed due to corrosion of its pivot mechanism, called the trunnion. This corrosion created excessive friction, causing the gate to become stuck at its hinges. When the hoist tried to raise the gate, the struts buckled, resulting in a collapse and an uncontrolled release of water.

How much money is estimated to be lost globally each year due to corrosion?

It is estimated that approximately two-and-a-half trillion dollars are lost annually worldwide due to the collective corrosion of materials and infrastructure.

What are some of the metals that are resistant to corrosion?

Noble metals like gold, silver, and platinum are highly resistant to corrosion because they are not reactive to atmospheric conditions like moisture and oxygen.

What is the basic process of corrosion?

Corrosion is an electrochemical reaction where a metal (the anode) is converted into a more stable form, typically an oxide. This occurs when the metal reacts with an electrolyte (like water or soil), leading to the transfer of electrons to the cathode. This results in the degradation of the metal.

What is an example of a metal alloy that resists corrosion due to passivation?

Stainless steel, especially grades like 304 and 316, are examples of metals that resist corrosion due to passivation. In this process, a protective oxide film forms on the metal's surface, preventing further degradation.

What role does the corrosion of steel play in the failure of infrastructure?

The corrosion of steel, particularly in reinforced concrete (where steel rebar rusts), can lead to internal stresses that cause cracking and spalling, severely compromising the structural integrity of buildings, bridges, and other infrastructure.

What is galvanic corrosion and how does it occur?

Galvanic corrosion occurs when two dissimilar metals come into contact, leading to one metal (the anode) corroding faster than the other (the cathode). This process happens when the metals are in an electrolyte, allowing an electrical current to flow between them.

How can material selection prevent corrosion in infrastructure?

Choosing materials that are less prone to corrosion or more resistant to certain conditions can significantly reduce the impact of corrosion. For example, using alloys like stainless steel or incorporating coatings can protect infrastructure from the effects of corrosion.

What is weathering steel, and how does it resist corrosion?

Weathering steel, also known as Corten steel, is an alloy that resists corrosion by allowing a layer of rust to form and remain attached. This protective layer slows further corrosion, making the steel more durable and requiring less maintenance over time.

What was the impact of corrosion management failure in Flint, Michigan?

In Flint, Michigan, the failure to properly manage corrosion led to water from the Flint River leaching lead from aging pipes, which exposed residents to harmful lead contamination. This resulted in a public health crisis, lawsuits, government firings, and long-term health issues for thousands of children.