Design Theories Of Strength Of Materials

The ability to withstand the applied stress of the materials without failure is called strength of a material. The strength of the material is referred to the stress-strain curve where the deformation cannot be reversed. The strength of the material is depending on the microstructure where the structure can alter in engineering process.

Types of loading:

• Transverse loading- The force is applied perpendicular to the longitudinal axis. Transverse loading make the material to bend and deflect the material to its original position, even the internal tensile and compressive change the curvature of the material.
• Axial Loading- The force is applied collinear to the longitudinal axis. Axial loading make the material either stretched or strained.
• Torsional Loading- The force is applied equal to external force and opposite to the parallel planes. It makes twisting action.
• Stress Terms

Stress is defined as force per unit area, where F is force and A is area acting per unit. The area may be deformed or unreformed but it depend on the stress which it used 

• Compressive Stress: The stress is caused by the applied force and it acts towards the reduced length of the material.
• Tensile stress: The Stress is caused by the applied force and it acts towards the elongate of the material. It is also caused by pulling the load.
• Shear Stress: The stress is caused by a opposing force and it acts toward the parallel line of the material.

Strength Terms:

Strength is defined as the material begins physically strong.

• Yield Strength: The minimum stress that makes the permanent deformation.
• Compressive strength: The stress makes the compressive failure of the material.
• Tensile Strength: The Stress applied makes the tensile failure of the material.
• Fatigue strength: It is used to measure the strength of the material.
• Impact strength: It is used to measure the capability of the material.

Strain (Deformation) Terms:

Deformation: When there is change in the shape of the applied material then the deformation is calculated by the displacement field of the material.

Strain: It is used to express the mathematical changes of the applied material.

Deflection: It is used to describe the magnitude of the bend surface.

Stress-strain Relationship:

The relationship is defined with elasticity and plasticity

Elasticity: The ability of the material to retain its original shape after the stress release.

Plasticity: The ability of the material to uncertain the original shape even after the stress releases.