Elastic and Plastic Deformation

What happens if you stretch a material past its elastic limit

It will be permanently stretched

What are the 2 types of deformation

Elastic deformation

Plastic deformation

Until their elastic limit how do materials act

Elastically

After their elastic limit how do materials act

Plastically

What does elastic mean

It will return to it’s original shape after undergoing a force

What does plastic mean

The material is permanently deformed and will not go back to its original shape.

What does the area under a force-extension graph show

The work done (elastic potential energy)

What does the load line represent

When the force has been added

What does the unloading line represent

When the force has been removed

How can you see if the material has been deformed plastically using its loading and unloading line

They don’t start and end at the same point

How can you calculate the work done to plastically deform the material

Calculate the area between the loading and unloading lines

What happens to the line after the limit of proportionality

It begins to curve