Is It a Stress vs Strain Plot or a Stress-Strain Curve?

[Ajwrighter]

1.
View attachment instructionsaj1.bmp
here is what I've obtained

Data:

View attachment dataaj1.bmp








3.

Increasing (με) (μin/in) and decreaseing (με) (μin/in) are both STRAIN
[Increasing σ (psi)] and decreaseing σ (psi) are both STRESS]


My question is. From the directions above, is it asking for a plot of Stress vs Strain or a Stress-Strain curve. And in either case. How many. Should I pool all the data together for one plot or for two? Or is it asking for both a plot and a curve?


further down it asks for: "use data from the most linear portion of the curve to calculate Modulus of the alloy using the following stress-strain equation (recall that the Modulus is the slope of the linear portion of the stress-strain curve, so the equation is the slope of a line)

To me this says to use a stress-strain curve. But why did it ask for a stress vs strain plot? I've spent way too long trying to interpret the directions.

 

[quantumdude]

You should make a stress-strain plot for the increasing loads, and a separate stress-strain plot for the decreasing loads. You are then asked whether the curve that best fits the data is linear. If so, then indicate such. If not, then identify the largest interval over which the data are approximately linear, and find the line of best fit (this is a necessary step in determining the modulus).

 

[piercas]

I understand your confusion with the directions. It seems like the instructions are not very clear and may be asking for both a plot and a curve. However, based on the information provided, it seems like the main objective is to create a stress-strain curve and calculate the modulus of the alloy using the linear portion of the curve.

In terms of the number of plots and curves, it is best to clarify with the person or source providing the instructions. If it is not specified, I would suggest creating both a plot and a curve to ensure all aspects are covered. Additionally, it may be helpful to pool all the data together for a more comprehensive analysis.

Overall, it is important to communicate clearly and precisely when giving instructions in scientific research, as it can save time and avoid confusion. If you are still unsure about the directions, it may be best to reach out to the person or source for clarification.