Stress/Strain What is the property in a material

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The discussion revolves around an experiment involving a broken aluminum sample, where the original gauge length was 50 mm, and elongation was measured to calculate strain. Participants are tasked with identifying a specific material property, such as ductility or tensile strength, and providing its numerical value based on the measurements. The challenges of determining the forces that caused the breakage are highlighted, as this complicates the analysis of the material properties. The conversation emphasizes the importance of understanding the relationship between strain and material properties in evaluating the sample's performance. Overall, the discussion underscores the complexities involved in analyzing material failure and the significance of accurate measurements.
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Homework Statement



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 that's what they want?

Thanks

Homework Equations





The Attempt at a Solution

 
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pat666 said:

Homework Statement



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 that's what they want?

Thanks

Homework Equations




The Attempt at a Solution


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

Peter
 
They weren't mentioned, we had to state them. THings like ductility, yield strength, youngs modulus, tensile strength etc
 
pat666 said:
They weren't mentioned, we had to state them. THings like ductility, yield strength, youngs modulus, tensile strength etc

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
 
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