ISO 37:2005 describes a method for the determination of the tensile stress-strain properties of vulcanized and thermoplastic rubbers. The properties which can be determined are tensile strength, elongation at break, stress at a given elongation, elongation at a given stress, stress at yield and elongation at yield. The measurement of stress and strain at yield applies only to some thermoplastic rubbers and certain other compounds.
A typical testing system would comprise of a 3300 series or 5500 series Universal testing machine, with either mechanical self-tightening, or pneumatic grips. An extensometer is usually required to measure specimen elongation, and a mechanical contacting extensometer could be used, or alternatively, a non-contact video extensometer can be used to measure the separation of gauge marks applied to the specimen.
Tensile Stress-Strain Properties of Vulcanized or Thermoplastic Rubber (ISO 37)