1. Dec 19, 2009

SOHAWONG

when the copper is stretched,does its young modules keep constant?
I am confused because the area will be decreased and the young modules is just related to the the material.

2. Dec 19, 2009

FredGarvin

Do you have a stress-strain diagram for copper? The modulus is the relation between the two (it is the slope of the plot). In other words, the modulus is the stiffness. When stretched, it will remain constant for a certain range (the elastic range). Once it passes that limit, it will not remain constant.

Generic Stress-Strain Curve:

Last edited: Dec 19, 2009
3. Dec 19, 2009

SOHAWONG

thx!The mind is clear now,but I don't under stand the lower half diagram