- The principle is essentially a dumbell shaped , test pieces are strained at a constant rate of traverse , and force and corrresponding extensions recorded .
- The forces reading are expressed as stresses by reference to the original sectional area of the test piece.
The following measurements can be be taken from a stress/strain curve for rubber :
- Tensile strength ( Stress at break ) – The maximum tensile stress reached in stretching tensile test piece to breaking point.
- Elongation at break ( Strain at break ) – Then tensile strain in the length at breaking point.
Young’s modulus : Ratio of stress to strain. The value can be obtained from the linear portion of the curve of the order of few percent.