Question

Hi I need Stress Strain Graphs to be made for the following data tables. There should be 3 graphs, one for each table. I also need to know what material each sample is made of. I assume this is calculated from calculating the Modulus of Elasticity E. However I do not really know. I appreciate everything. The data tables are below this post.

Include the Following

• Stress Strain graphs for each sample showing what variable and unit you have on both axes, and stating if it is sample 1, 2 or 3. Show the points in the graph and additionally a trendline.
• Explain how you got your conclusion (i.e., show your work) including how it was calculated/how you got it, what value it had and what you compared with.
• Your conclusion of what each of the three samples are made of.  

Sample 1
Strain [mm/mm]	Stress [MPa]
0.0019	509.2958069
0.0019	530.5164795
0.00198	558.8106689
0.0021	583.5681152
0.00216	601.2520142
0.00228	622.4726563
0.00242	604.7887573
0.00242	604.7887573
0.0025	647.2301025
0.00268	684.9140015
0.0027	699.5978394
0.00272	720.2817383

Sample 2
Strain [mm/mm]	Stress [MPa]
0.0004	17.68388176
0.00096	38.90454102
0.00104	60.12520218
0.00162	81.34586334
0.0018	99.02973938
0.00204	116.713623
0.0024	134.3975067
0.0026	152.0813904
0.00306	173.3020477
0.00342	194.5227051
0.00366	212.2065887
0.00398	229.8904724

Sample 3
Strain [mm/mm]	Stress [MPa]
0.00088	31.68388
0.00098	35.36776
0.00122	93.58842
0.00132	102.5665
0.0019	130.8607
0.002	130.8607
0.0021	183.9124
0.0024	201.5963
0.0026	222.8169
0.00278	244.0376
0.00322	265.2582
0.00358	282.9421

Answer 1

I I have drawn the graphs using MS-Excel.

on application of load in UTM(UNIVERSAL TESTING MACHINE) on a material strains are calculated using the strain gauge attached to the material and stress are calculated from load/cross sectional area of the material.

we cannot predict exactly what the material is. but we can say the nature of the material

case 1: the sample 1 is has very less increase in stress upon strain this indicates sample 1 is plastic.

case 2: sample 2 is elastic, stress is proportional to strain

case 3: sample 3 is also an elastic material but the cross sectional area of testing sample is varying.

Ductile materials have plastic zone and elastic limit where as the brittle materials stress strain graph starts with the elastic limit and do not posses any plastic zone. by this we can also conclude sample 1 is a ductile material since it is in plastic zone.