How to Measure Tensile Strength Using a Tensile Testing Machine
Obtain a long, thin piece of your material., Using calipers, carefully measure the diameter of the sample., Calculate the cross-sectional area of the sample., Thread one end of your sample through the grips at the base of the machine., Measure the...
Step-by-Step Guide
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Step 1: Obtain a long
For example: you may use a strand of hair, yarn, medical sutures, sewing thread, etc. -
Step 2: thin piece of your material.
Ensure that you do not clamp the calipers too hard around the sample in order to ensure you are taking an accurate measurement. , Use the formula A=π*r^2.
You will have to divide the measured diameter in half in order to find the radius.
Make sure that you are using the correct units; you will have to convert the original measurement from millimeters to meters., When secured at the bottom, clamp the other end of the material to the top of the base.
Make sure that your sample is taut, but not stretched. , The measured section should be from the point of contact at the bottom of the base to the point of contact at the top. , This is the number of millimeters per minute that the machine will move, separating the top and bottom pieces of the base in order to stretch your sample.
On the test stand, press the leftmost button for "menu," and scroll through the options using the designated buttons.
On the strain rate slide, press the middle two buttons to increase or decrease the strain rate as desired.
Press the rightmost button to enter the strain rate. , At the bottom of the screen, check “invert load” in order to correctly graph your travel vs. load curve. , The machine will pull the sample at the designated strain rate., The software will continue recording, but you will disregard the data collected after the sample breaks. , You will see a graph of load vs. travel.
On the left-hand side, you will see a data table.
From this data, you will find the maximum force the machine applied to your sample.
Press the circle button on the tensile testing machine to end the trial., You will be asked where you would like to save the file.
Save it to your desktop, a flash drive, or any designated place on your computer.
The data will be saved in a .txt file. , You may use software such as Microsoft Excel or Google Sheets.
Once the data from the .txt file has been copied into the document, add in the cross-sectional area and original length of the sample. , This is done by “normalizing” the data, specifically by zeroing the travel from the start time.
This is completed by using a code to subtract the adjacent cell by the initial reading value of the travel.
This code utilizes the ‘$’ sign to ensure the initial reading value is fixed, and then the code is copied to all cells in the column corresponding with the remaining data data. , This is done by creating a code to divide the change in length data by the original length.
The ‘$’ is again used to fix the original length value, and the code is copied for all corresponding cells in the column.
As strain is unitless, the original values were kept in millimeters. , This code also utilizes the ‘$’ symbol to ensure that the value of the cell remains the same when copying the code into the rest of the column.
As the number outputted was quite large, it was converted into megapascals by dividing by 10^6.
Note that the units for load are Newtons and the units for cross-sectional area are in square meters. , This can be achieved using the graphing features of excel. -
Step 3: Using calipers
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Step 4: carefully measure the diameter of the sample.
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Step 5: Calculate the cross-sectional area of the sample.
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Step 6: Thread one end of your sample through the grips at the base of the machine.
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Step 7: Measure the initial length of the sample in the machine using the calipers.
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Step 8: Select your strain rate.
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Step 9: Open the software on your computer.
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Step 10: Click start on the software
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Step 11: then press the up arrow button on the tensile testing machine.
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Step 12: Let the trial run until the sample breaks.
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Step 13: Click the stop button on the computer software.
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Step 14: Click the save button on the computer software.
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Step 15: Copy the data from the .txt file into a spreadsheet document.
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Step 16: Adjust the travel data to represent change in length over time.
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Step 17: Find strain using the change in length data.
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Step 18: Calculate stress by writing a code to divide the load by the cross-sectional area.
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Step 19: Graph the stress-strain curve (optional).
Detailed Guide
For example: you may use a strand of hair, yarn, medical sutures, sewing thread, etc.
Ensure that you do not clamp the calipers too hard around the sample in order to ensure you are taking an accurate measurement. , Use the formula A=π*r^2.
You will have to divide the measured diameter in half in order to find the radius.
Make sure that you are using the correct units; you will have to convert the original measurement from millimeters to meters., When secured at the bottom, clamp the other end of the material to the top of the base.
Make sure that your sample is taut, but not stretched. , The measured section should be from the point of contact at the bottom of the base to the point of contact at the top. , This is the number of millimeters per minute that the machine will move, separating the top and bottom pieces of the base in order to stretch your sample.
On the test stand, press the leftmost button for "menu," and scroll through the options using the designated buttons.
On the strain rate slide, press the middle two buttons to increase or decrease the strain rate as desired.
Press the rightmost button to enter the strain rate. , At the bottom of the screen, check “invert load” in order to correctly graph your travel vs. load curve. , The machine will pull the sample at the designated strain rate., The software will continue recording, but you will disregard the data collected after the sample breaks. , You will see a graph of load vs. travel.
On the left-hand side, you will see a data table.
From this data, you will find the maximum force the machine applied to your sample.
Press the circle button on the tensile testing machine to end the trial., You will be asked where you would like to save the file.
Save it to your desktop, a flash drive, or any designated place on your computer.
The data will be saved in a .txt file. , You may use software such as Microsoft Excel or Google Sheets.
Once the data from the .txt file has been copied into the document, add in the cross-sectional area and original length of the sample. , This is done by “normalizing” the data, specifically by zeroing the travel from the start time.
This is completed by using a code to subtract the adjacent cell by the initial reading value of the travel.
This code utilizes the ‘$’ sign to ensure the initial reading value is fixed, and then the code is copied to all cells in the column corresponding with the remaining data data. , This is done by creating a code to divide the change in length data by the original length.
The ‘$’ is again used to fix the original length value, and the code is copied for all corresponding cells in the column.
As strain is unitless, the original values were kept in millimeters. , This code also utilizes the ‘$’ symbol to ensure that the value of the cell remains the same when copying the code into the rest of the column.
As the number outputted was quite large, it was converted into megapascals by dividing by 10^6.
Note that the units for load are Newtons and the units for cross-sectional area are in square meters. , This can be achieved using the graphing features of excel.
About the Author
Victoria Murphy
A passionate writer with expertise in pet care topics. Loves sharing practical knowledge.
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