Charpy Impact Test Report

Table of Contents
Statement of Intent…………………………………………………………………………………..3
Background……………………………………………………………………………………………….3
Equipment…………………………………………………………………………………………………5
Procedure………………………………………………………………………………………………….6
Data and Analysis………………………………………………………………………………………7
Conclusions……………………………………………………………………………………………….11
Works Cited………………………………………………………………………………………………12

Statement of Intent The purpose of the experiment was to run a Charpy Impact Test and compare the energy absorbed between 4130 steel and A36 hot rolled steel and find the ductile to brittle transition for each.
Background
The Charpy test works by suspending a notched specimen at both ends and then breaking the specimen by …show more content…

The only outliers are at points 9 and 20. Without those outliers, the graph does have a vague shape of the typical DTBT graph. Although the data determines that the DTBT starts at -90°F with 18ft-lb of energy absorbed, the standard is -30°F with 30ft-lb of energy absorbed.(Norsok 75) As shown in Figure 6, these are the samples lined up from coldest to warmest. You can see the DTBT. It starts at sample 5 and ends at sample 8 or 9.

Figure 5

Figure 6
Conclusion
In conclusion, the data collected was flawed for reasons known and unknown. The graphs of the data did not come close to what a DTBT is supposed to be, though the 4130 steel was much closer to what it was supposed to look like. One error could have been human error in taking the temperatures of each sample. The contact thermometer might not have had complete contact with the sample. Another error that we had was how we handled the samples. While looking up the Charpy Impact Test, it said to bathe the centering tongs in the same medium as the sample is in so that they do not steal heat or heat up the sample.(Anderson 139)
Another error is the time it took to measure the temperature and place the sample in the testing machine and run the test. The test calls for a 5 second window. Sometimes it took too long to measure the temperature or it took too long to place the sample precisely in the testing machine. Also, it took