Stainless Steel Tubing, Advanced Video Extensometers, Tensile Testing
Stainless steel tubing (or any other variety of rigid metallic tubing) can be difficult to test in tension for two reasons. The first is that standard methods of gripping will cause the tubing to collapse and lead to pre-mature failure of the specimen. The second is strain measurement is usually not possible with traditional clip-on extensometers since the knife-edges lead to high-stress concentrations and consequently failure of the thin specimen wall. The purpose of this testing was to recommend a gripping solution and evaluate the use of the Advanced Video Extensometer (AVE) for accurate, non-contacting strain measurement.
For this test we used a 5582 tensile testing system configured with 30kN wedge grips with Vee-serrated faces, and an AVE with 200 mm Field of View (FOV) lens. We inserted solid mandrels, that matched the inner diameter of the specimens, into the gripped ends to encourage failure within the gauge area. Additionally, we used a white paint pen to mark the specimen gauge area for strain measurement with the AVE. The AVE set up window in our Bluehill® Software demonstrates the relationship between the marks on the specimen and the marks captured by the AVE before the start of a test.
In conclusion, these results show that the gripping and marking techniques were able to accurately measure tensile load and axial strain through failure in each specimen.
5900 Universal Testing Systems are engineered for precision, built for durability, and offer the flexibility for changing requirements. They are designed with standard and optional features that increase testing efficiency and improve the testing experience for the operator. A wide range of models are available for testing capacities from < 100N up to 600kN.
- 6.8 MB
Bluehill Universal Software is built from the ground-up for touch interaction and an intuitive user experience. Discover simpler and smarter testing with features such as pre-loaded test methods, QuickTest in seconds, enhanced data exporting: and Instron Connect – a new feature that provides a direct communication link to Service. Users of previous versions of software such as Bluehill 2 and Bluehill 3 can easily upgrade to the newest version of Bluehill.
- 2.6 MB