# Stress/Strain What is the property in a material

1. Jul 29, 2011

### pat666

1. The problem statement, all variables and given/known data

In an experiment we were given a broken piece of alluminium that was (before broken) 50mm long. Then we measured it and found the elongation. From this it is pretty easy to calculate the strain. What does this actually tell me about the material though?. Actual Question:

The original gauge length of the sample is 50 mm. Establish the extended [failed]
gauge length of the each sample with a ruler from the gauge length marks on the
sample. [The gauge marks are a single centre punch mark at each end on the sample.]
This refers to a material property requested in Question 4a. Name this material
property and give its numerical value. As you have been supplied a number of
samples discuss the failures and the validity of the results obtained.

I have an actual value for strain if thats what they want?

Thanks
2. Relevant equations

3. The attempt at a solution

2. Jul 29, 2011

### PeterO

What were the "material properties mentioned in Question 4a" ?

Peter

3. Jul 29, 2011

### pat666

They weren't mentioned, we had to state them. THings like ductility, yield strength, youngs modulus, tensile strength etc

4. Jul 29, 2011

### PeterO

Sorry, I was picking up on, "This refers to a material property requested in Question 4a"

If you have broken samples, it is often difficult to work out what forces were applied in various directions in order to break them, So I geuss any material property that refers to, or involves, the size of any force(s) involved would be out of the question???

Peter