Analysis and plotting of Stress$-$Strain With Tensile Test Data:

$5\mathrm{.}11$ A tensile testing machine such as the one shown in Figure P$5\mathrm{.}11$ is used

to determine the behavior of materials as they are deformed. In the typical

test, a specimen is suretched at a steady rate. The force $($load$)$ required to

deform the material is measured, as is the resulting detormation. An cxam$-$

Table P$5.11$ Tensile Tesling Dato

can be used to calculate the applied stress and the resulting strain with the

following equations.

$=\frac{F}{A},$ and $,=\frac{l-b_0}{b_0}$

where

$=$ suress in $I\frac{b_f}{i}{n}^2($psi$)$

A $-$ simple cross$-$sectional area in in$.?$

$-$ stain in in$./$in$.$

$b_0-$ sample length

$($a$)$ Use the provided data to calculate the stress aud the corresponding

statin for cach data pair, The tested sample was a rod of diameter

$0\mathrm{.}505$ in$,$ so you'll need on find the cross$-$sectional arca to use in your

Calculations.

$($b$)$ Create an $x-$y plot with strain on the waxis and stress on the y$-$axis

Connect the data points with a solid black line, and use circles to mark

each data point

$($c$)$ Add a title and appropriate axis labels

$($d$)$ The point where the graph changes from a straight line with a steep

slope to a flattened curve is called the yield stress or yield point. This

corresponds to at significant change in the material behavior. Before the

yeld point the material is elastic, returning to its original shape if the

load is removed$-$much like a rubber band. Once the material has been

nent and is called plastic deformation. Use a text box to mark the vield

point on your graph.

$\%$ Plot and Analyze Data from Tensile Testing Machine

format shorteng $\%$ formats output to $4$ decimals, engineering notation

$F=[l]\%$ type values inside $[]$ to enter the vector of applied Forces $(1$oad$),1$ bf $=$ pounds

$L=[,]$;$\%$ type values inside $[]$ to enter the vector of sample lengths, ins.

$d=$;$\%$ add a value here fpr the rod diameter, ins. $($given$)$

$A=(,)$;$\%$ add code inside $()$ to calculate the cross sectional area $($in$^2)$ of rod, use $A=\frac{1}{4}(p1)d^{{?}^{{?}^{?}}}2$

$\%L(1)=$ original sample length $=2\mathrm{.}0$ ins. Indexed from vector $L$

$L0=L(1)$;$\%$ original sample length $=2\mathrm{.}0$ ins. Lo is indexed from vector $L$ as $L(1)$

$e=(,)$;$\%$ add code inside $()$ to calculate strain $($epsilon$),$ in$/$in as shown on the problem description

sigma $=$;$\%$ add code here to calculate stress, lbf$/$in$`2($psi$)($don$\text{'}$t forget the $./$ vector division operator$)$

figure $\%$ generates plot

$\%$ b$.)$ create an $x-y$ plot with strain on the $x-$axis and stress on the $y-$axis $...$

$\%$ connect the data points with a solid black line and use circles to mark each data point

plot $()\%$ add code inside $()$ to generate the specified plot in part b$.),$ above

$$ c$.)$ Add a title and appropriate $x-$axis and $y-$axis labels. Show all units

xlabel $(\text{'}")$; ylabel $(\text{'}\text{'})$

title $(\text{'}\text{'})\%$ figure title

str $\text{'}\text{'}\}$; $$ add code inside $\{\text{'}"\}$ to create a string variable named 'Yield point"

dim e $0$