MATERIAL: Mild Steel, 0.1% carbon, normalised at 900°C SPECIMEN: 5mm diameter (nominal) TENSILE TESTING OF MILD STEEL 11.0 PROCEDURE: 6.8 to 7.0 20 mm 05.04 to 5.06 Radius 1.5 +0.0 -0.2

60 mm 20 mm 110 mm Figure 1: Tensile specimen, all dimensions in mm. EXTENSOMETER: 25mm gauge length clip on extensometer. Elastic Region 1. With the data acquisition set to record the load (N) from the load cell and extension/ mm from the extensometer, start the control software and load the mounted specimen axially up to a load of 4 kN and then unload the specimen to zero load. Plastic Region 2. Repeat the procedure as above but continue loading until a yield target of 0.4% observing in real-time the sample yield. 3. Unload the sample again to zero load and take note of the samples permanent set. 4. Remove the Extensometer to avoid damage during the final part of the experiment. Ductile Region 5. Reload the specimen to fracture while recording the corresponding load (N) to the machine's crosshead displacement (mm). 6. Observe how ductile the sample is in real-time. Failure 7. Take final measurements of the test sample, noting the tested elongation length and the diameter at the point of necking, and take images of the fracture surfaces. POST-TEST ANALYSIS From the downloaded Load / Extensometer data, plot a Stress/Strain linear graph to find the modulus of elasticity, E; • From the downloaded Load / Crosshead displacement data, plot the characteristic Stress/Strain curve for the 0.1% carbon steel sample and on the graph estimate: o The Upper Yield Point o The Lower Yield Point/nExperimentation Precise details of items under test, and of the testing system, are required. Sketches, circuit diagrams, and/or CAD drawings are often required in this section. All equipment should be specified fully (i.e. using model numbers, and reference numbers if possible) with the exception of minor ancillary equipment such as a metre rule, protractor etc. This specification may also include the accuracy of the equipment used. Always remember that at some future date the experimental results may be subject to severe scrutiny and the more accurately the system has been specified the less the doubt concerning the test, and the better the chance of remedial action. Concise details of the operations performed should be presented mentioning factors which are of special significance. Trivial statements however should be avoided, but, for example, where the order of performing a number of steps is considered to be important such information should be concisely presented. The writing style should resemble a recipe in a cookbook. It is particularly useful to refer to special precautions taken as this can often eliminate possible doubts in a future enquiry. The purpose of this section is to define the experimental techniques employed without ambiguity, and thus in a way which would permit a complete identical "re-test". Remember it was done in the past.