Manufacturers of metals, including producers of raw material or finished metal products, need to pass compliance standards before shipping their product. Tensile testing is imperative for ensuring a safe, high quality material and avoiding the major liabilities associated with providing non-compliant products. These actions will keep the end consumer satisfied and dramatically reduce the chance of failure in the field. Below, we will discuss ASTM E8, an international standard for determining the tensile strength of metals.
ASTM E8: Specification for Measuring Tensile Strength of Metals
The ASTM E8 test provides data on the strength and ductility of metals under uniaxial tensile forces. The tensile strength of a metal is essentially its ability to withstand tensile loads without failure. Ductility, on the other hand, measures a material’s ability to deform under tensile stresses. This is an important factor in metal forming processes since brittle metals are more likely to rupture. Metals that break or crack when stressed cannot be transformed during hammering, rolling, or drawing.
Technicians who conduct tensile testing of metals measure a number of mechanical properties to determine the material’s quality. The figure below is a stress-strain curve which provides a graphical representation of these mechanical properties. Some of the critical measurements include: peak stress or ultimate tensile strength (Point D), rupture or fracture point (Z), offset yield strength (B), and percent elongation at break.