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Note that 1018 steel has a lower and upper yield that should be taken directly from the plot AND the yield stress for the acrylic sample will be identical to the UTS since this is a brittle material 5. Include plots showing the offset method used to calculate yield stress for 6061 Al and AR 400 steel. Engineering Strain for each of the raw data sets. If you do remove a sample from the data set, calculate the new Mean and STDV. Indicate which samples you would remove from the data set based on Chauvenet's Criterion and indicate why you would do so.
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Perform Chauvenet's Criterion on the new data set (the data set that includes the data you calculated). You should make a table showing the results calculated. Include the data you calculated from the raw data with the data provided from past tests. Calculate the Mean and STDV of E, Oy, OUTS, and %EL for each sample. Yield Stress (Gy) - upper and lower Yield Stress for the 1018 Steel sample. You are required to analyze this data and calculate the following for each of the 4 materials (ie. 1 is really the change in length of the sample over a 1-inch distance of the sample gauge length. 1 is the distance, in me, that the extensometer has displaced during the test. 1 Force is the data collected from the load cell, this is how much force is being applied to the sample.
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The columns you need to analyze are force and Ext. The raw data provided on DL has 5 columns: Time, Force, Stroke, Ext. Data was collocted for you to analyze Data Analysis (complete and turn into D21.) 1. Each sample was loaded at the indicated crosshead rate until the sample fractured. For our experiment, the metals were tested with a crosshead speed of Smin and the acrylic was tested at Imm/min. Many materials have strain rate sensitivity, so pulling too fast can produce high strain rate properties instead of quasi-static properties. A typical rule of thumb is to limit the crosshead speed so the sample breaks in 1-5min. The gauge width and thickness for each sample has been measured with dial calipers. A load cell measures the amount of force that is being applied to the sample and the computer records the data from the load cell and extensometer which measures the length change of the sample over a 1 inch length at the center of the "dog bone" sample Procedure 1. A crosshead moves vertically to apply tension to the test sample/specimen. Figure 2: A universal testing machine for axial tensile tests. Acrylic Each sample was placed in the holding grips (see Fig. Table shows the dimensions per standard ASTM E The sample has large shoulders that are gripped in the tensile testing machine and deformation occurs in the more narrow gauge sectionĮxperiment One sample of four material types have been tested with the Shimadzu Universal Testing Machine: 1. B D А Dimension B D C(min) F (min.) Amin.) Elmin.) Length (in) 0.75 0.5 2.25 0.25 8 2 Figure 11 Standard dog bone" tensile test sample. 1), at a fixed strain rate until it fractures. The mechanical properties of a material that is subject to an axial stress are obtained by pulling a specimen, typically **dog bone" shaped (see Fig. This is a common method for obtaining mechanical properties of isotropic materials. Transcribed image text: Tensile Testing Background: A tensile test is a universal test where a sample is subjected to an axial tensile load until failure.