Tensile Testing

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Stain 6 = 0.0320

Stain 7 = 0.0410

Stain 8 = 0.0504

Stain 9 = 0.0602

Stain 10 = 0.0705

Stain 11 = 0.1081

From the analysis of the results, it is clear the strain keep on increasing with the increase of the loading and the stress value. The loading increases the elongation length of the specimen and this indicates the increase in the strain level in each case. The elongation is referenced from the initial length and this is the main reason for the increase in the elongation and strain levels. The strain 1 is less than strain two and this goes on up to the strain 11 that is the highest. The increase of the load is able to increase the stress applied and this moves the specimen towards the fracture point. This will be achieved when the elongation cannot be increased any further and therefore fracture.

After attaining the results, load vs. elongation applied graph was plotted as shown below;

[pic 1]

From the above graph, it is clear that an increase in loading leads to an increase in the elongation. This means that the more loading is applied, the specimen tends to move to the fracture point. The loading is therefore able to increase the stress applied on the specimen and therefore meaning that the specimen will reach a point where it cannot be able to carry the loading and therefore the fracture point. In addition, from the graph, it is clear that the different loadings are able to lead different elongation lengths based on the load which is applied. Moreover, it has to be noted that the same specimen is used in each case and this leads to an addition on the elongation in each loading case. The result can show that the specimen is unable to attain further high elongation even with higher load being applied. This means that the plastic state of the specimen is reached and it tends to the fracture level.

Analysis of the stress vs. strain graph

The increase of the stress is able to lead to an increase to the strain level up to a level when the specimen cannot be elongated further. This means that the graph is able to curve downwards since the elongation rate is able to reduce. The reduction on the elongation rate is able to reduce the strain level even with the addition of the stress value on the case. After the fracture point, the specimen is able to attain no farther elongation and this means that the strain level is not available.

[pic 2]

The initial elongation range is known as the elastic range when the increase in the stress level is able to lead to noticeable increase in strain. The next level is able to amount to slow increase in the strain even with mountable increase in the stress level. The further increase in the stress level is able to lead to slow and even negative sloping of the graph since the strain level is able to lead. This continues until the fracture point is achieved and the material cannot elongate anymore.

The yield strength

The stress value of the specimen is found through the analysis of the loading and the area of the specimen. The yield strength is found at a point when the maximum elongation is found at which is able to happen at the end of the elastic point of the strain vs stress graph. This point is able to provide the required yield stress which is key to find the yield strength of the material. After finding the, yield strength, the tensile strength is found through the use of the maximum loading case and the area of the specimen. The loading case, which is able to attract the highest percentage increase in the elongation, is used in the yield strength calculation.