What is Strain Rate?

About Strain Rate:

• Strain is how much a material deforms when stress is applied. It is a measure of the change in shape or size of an object relative to its original shape or size.
  • It has units of meters divided by meters, so it ends up without physical units.
• Strain rate is the rate of deformationcaused by strain in a material within a corresponding time. 
  • It is a measure of how quickly a material is deformed over time.
  • It involves both the rate wherein a certain material expands and shears.
  • Strain Rate = Change in Strain / Change in Time
  • The unit of strain rate is per second. 
• Importance:
  • It is an important factor in materials science and engineering because it influences the mechanical properties and behavior of materials.
  • It can be highly beneficial in the field of metallurgy and corrosion engineering.
  • Since materials may undergo deformation in various rates and directions, learning how to gauge strain rate with respect to certain elements like time, velocity, and others is vital in determining the material strength and the point at which corrosion, specifically stress corrosion cracking, could take place.
  • The use of low strain rates is now a widely used technique in evaluating the response of materials against stress.

Q1: What is corrosion?

Corrosion is the process of decay on a material caused by a chemical reaction to its environment. The reaction is typically in the form of oxidation. Corrosion of metal occurs when an exposed surface comes in contact with a gas or liquid, and the process is accelerated by exposure to warm temperatures, acids, and salts. Most metals are susceptible to corrosion, but all materials are subject to degradation. For example, corrosion of the polymers used to insulate coatings on electrical wiring has been a concern in older airplanes.

Source: Copper becomes unexpectedly hard under extreme strain rate