Young modulus for pure copper

1

Young’s modulus for copper is in the literature from 110 to 130GPa, but from the tensile test I get about 13GPa, what could be the reason for the difference?

"Table 4. Tensile test results for pure copper. " from this article: https://www.researchgate.net/publication/282179758_Experimental_analysis_of_microstructure_and_mechanical_properties_of_copper_and_brass_based_alloys

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Young modulus betwen point (No.) 4 and 3 is 11GPa, why?

[(228,657-126,385)/(1,458-0,544)]*100/1000

*100 → change from strain % to mm/mm
/1000 → change from MPa to GPa

2

I get around 28 GPa from the initial linear portion. But I would look for more articles to confirm this.

stress-strain
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3

I’d say wrong units…Also a yield stress of 300 MPa is unlikely. Properties of copper and copper alloys at cryogenic temperatures (nist.gov)

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4

From: Applied Sciences | Free Full-Text | Comparison of Tensile and Fatigue Properties of Copper Thin Film Depending on Process Method

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E~61GPa

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6

This yield strength is due to strain hardening. Only achievable in thin specimens without fracture probably. Maybe that’s the reason for the low elastic modulus. What shape are you looking for? Thin sheets? Annealed? Hardened?

7

Maybe this one can provide a better answer to your question. I was focusing on macro engineering world…

Elucidating the crystallographic orientation of the foils is important for understanding the measurement results of E because E is strongly influenced by the crystallographic orien

Look interesting the problem you are looking into…

8

There are many stress-strain curves for copper and other materials in the “Atlas of Stress-Strain Curves”. This book can be quite useful for FEA.

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9

Thank you very much for the link, I need to designate a Young module for 3.15x2.24mm copper wire, which is used in electric motors (and I’m new to copper).

10

I guess that this also shows well that the approach we often use when there’s no test data for simulations may be more inaccurate than one could expect.

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11

I’m not a specialist either, but I’ve done some structural analysis of space components with electronic/electrical copper pads the size being similar to your wire and they gave to me mechanical properties for the copper like macroscopic values you find in matweb, around 110 GPa for Young modulus and yield strength that of annealed condition…measuring wires looks like a science by itself:https://link.springer.com/content/pdf/10.1007/s13320-019-0531-3.pdf

12

The label “pure copper” in the report is somewhat misleading. It contains 0.5% zinc. In my opinion the whole report is incoherent to the point of being unreadable.