Stress and Strain

Jamie Z 2025-04-22

Stress

• Stress is the internal pressure within a component or material. It is a measure of the force applied to an area and is calculated using the equation:

Stress = F/A

• σ denotes stress and is expressed as Pascals (Pa)

• F is the applied force in Newtons (N)

• A is the material area supporting that force in square metres (m^2)

• The Yield Stress for this material is 250 MPa

• The Ultimate Stress for this material is 400 MPa

• The material is Elastic up to 250 MPa and is Ductile afterwards

• The material has a straight-line portion (the Elastic Range) and therefore obeys Hooke’s Law

• The Elastic Modulus for the material is 250 MPa / (0.12% / 100) = 208,000 MPa = 208 GPa

• The area under the entire graph gives an indication of Toughness