Tensile Testing Lab

The tensile test involves applying an ever-increasing load up to the final failure of the test sample. The tensile strength is the maximum load divided by the original cross-sectional area of the test sample. The yield strength relates to the load at which plastic deformation or yielding begins. There are three criteria used to define the initiation of yielding. These properties are the elastic limit, the proportional limit, and the yield strength.

The top and bottom grips attached to the tensile tester secure the test sample. During the tension test, the grips are moved apart at a constant rate to pull and stretch the specimen. The force on the specimen and its displacement is continuously monitored and plotted on a stress-strain curve until failure. After the tensile test specimen has broken, the technician calculates the measurements, tensile strength, yield strength, and ductility. The fractured sample’s combined lengths are compared to the pre-test sample length to determine elongation. The original cross-section measurement is also compared to the final cross-section to obtain the reduction in area.

Elevated temperature tensile testing is a subset method of evaluating the behavior of materials under a combination of heat and tension. When performing an elevated temperature tensile test, the specimen is placed inside a furnace on our test carousel, capable of processing up to three specimens at a time. Our computer-controlled system heats the specimen to the required temperature, then allows it to soak. Next, the specimen loads into the test frame, where an extensometer in the latest design measures the strain on the specimen as the load increases. Similarly, cryogenic tensile testing on round and flat specimens is also an option to evaluate the properties exhibited by materials cooled in liquid nitrogen (LN2) to -320°F.
See the test in action.

We use an optical non-contact extensometer for our 60K tensile machine to provide more testing options. This machine is ideal for non-contact measurement of axial strain and displacement. Its high resolution and ISO 0,5 / ASTM B-1 accuracy classes make it suitable for non-contact measurement of a wide range of strain values, including tiny strains required to measure the modulus of metals. The non-contact extensometer is also ideal for testing brittle, porous, and additively manufactured materials.