ISO 6892 specifies the method for tensile testing metallic materials and defines the mechanical properties that can be determined at ambient temperature. The test involves straining a test piece in tension, generally to failure, for the purpose of determining one or more mechanical properties. Products that may be tested in accordance with this standard include metallic sheets, plates, wires, bars, and tubes. Specimens are gripped to ensure that the specimen is aligned axially to minimize bending. The specimen is then strained in tension until failure, and load and strain data are recorded.
The standard provides two methods for testing specimens. The first method uses strain rate control to minimize the variation of strain rates during the determination of strain rate sensitive parameters, while the second method a testing rate that is based on the stress rate. The choice of method and rates are at the discretion of the test laboratory, but should be clearly stated when reporting test results.
The standard also includes recommendations for specimen types and dimensions, advice concerning the use of computer-controlled tensile testing machines, and methods for estimating the uncertainty of measurement. Results determined typically include yield, proof strengths, ultimate tensile strength, and elongation at fracture.
A typical testing system will include a universal testing machine, such as our 5900 Series, with suitable wedge or hydraulic grips, and a clip-on or automatic extensometer. Here, we tested metal dogbones using 250 kN DuraSync grips and our automatic contacting extensometer, the AutoX 750. The AutoX 750 in combination with Bluehill® 3.31 is fully capable of automatic strain control.
We recommend that you read and review the standard in full to ensure a complete understanding of the test methods and required results.