Tensile Test (Lab Report Sample)

American International University
School of Engineering and Computing
Mechanical Engineering Department
EC-102 Materials Science for Engineering Applications Laboratory
Experiment One: Tensile Test
Title............................................................................................................................. 3
Objective....................................................................................................................... 4
Theory............................................................................................................................ 4
Apparatus ..................................................................................................................... 8
Procedure ..................................................................................................................... 7
Results......................................................................................................................... 7
Analysis ...................................................................................................................... 8
Discussion .................................................................................................................. 10
Conclusion................................................................................................................... 11 References................................................................................................................... 11
Figure 1: shear stress - shear strain diagram for ductile material ............................ 5
Figure 2: Apparatus Parts........................................................................................... 6
Figure 3: Specimen Details. ....................................................................................... 6
TOC \o "1-1" \h \z \u Table 1: Specimen data PAGEREF _Toc86926723 \h 7 Table 2: data collected from the tensile test. PAGEREF _Toc86926724 \h 9
The mechanical parameters of a material govern its utility and influence the service that may be expected. This entailed deformation or fracture under various stresses, temperatures, times, and other circumstances. Structure considers modulus of elasticity, yield point, ultimate tensile strength, plasticity, toughness, ductility, and fracture. The goal of the investigation is to look at the qualities of steel, a common structural material.
* To find out how a material reacts when it is exposed to a tensile load.
* The major goal of the experiment was to use a universal testing equipment to examine the tensile characteristics of Carbon steel. Tensile strength, yield stress, and young's modulus were among the material parameters examined.
Physical qualities define the majority of engineering materials. Ultimate tensile strength, modulus of resilience, modulus of toughness, yield strength, and modulus of elasticity are some of these qualities. The aforesaid attributes are therefore relevant to all situations of that material undergoing similar stress after being identified by means of the experiment, enabling for the construction of structural components with predictable behavior. Most of these properties are influenced by external factors such as temperature, loading frequency, and material purity in real life. The existence of impurities and faults has an impact on the material's varied qualities, either positively or adversely.
On the other side, the existence of faults in the material has a detrimental impact on the material's characteristics, which might lead to unexpected failure or behavior. Temperature is occasionally adjusted numerically to counteract these negative impacts, and the design of safety is taken into account throughout the design stage to account for the uncertainties and unpredictable loads, guaranteeing that the material does not fail. The materials are also put through a series of tests to verify that they are in good mechanical condition.
To define the sort of load and the range within which materials are safe, recognized material attributes are generally relied upon. Strength, toughness, brittleness, and other related characteristics can be compared using the attributes. The needed data for a stress-strain graph can be produced by performing a tensile test with an axial load.
The Young's modulus or modulus of elasticity gives the relationship that exists between strain and stress for all stresses that is below the limit of proportionality. The true stress is given by the amount of load applied divided by cross sectional area after taking into consideration the change in area due to the deformation. The modulus of resilience is a measure of a material's capacity to absorb energy without deforming plastically. The real stress is calculated by dividing the applied load by the cross sectional area. The ultimate change in length of a sample that has already reached failure is calculated using percentage elongation at failure.
The modulus of toughness describes the amount of work done on a unit volume starting at zero stress and ending at failure. The modulus of resilience is a measure of a material's capacity to absorb energy without deforming plastically. The applied load is divided by the material's original cross sectional area to calculate engineering stress. After taking into account the change in area due to deformation, the real stress is calculated as the amount of force applied divided by cross sectional area. The change in length divided by the original gauge length called engineering strain. The natural log of the fin, on the other hand, gives the genuine strain at the point of rapture.
The stress-strain graph may be used to determine an engineering material's primary mechanical characteristics. When properly examined, these qualities define a material's mechanical performance when subjected to a load and apply to all types of engineering materials.
* Yield Stress: σY = load at yield point original area
* Tensile Strength: σTS = maximum load original area
* Young’s Modulus: E = ∆σ∆ε
Finally, the percentage elongation experienced by a material up to its breaking point is used to determine its ductility. The change in length of the material at the conclusion of the test is usually used to determine this.
Figure 2: shear stress - shear strain diagram for ductile material
The shear stress shear strain diagram for ductile material
Where:
O-A: Elastic region, linear relation between