Creep & Stress Rupture Testing
Creep and rupture tests are essential to evaluate the time-dependent behavior of metals and composites at elevated temperatures under applied stress. Deformation is measured as a function of time.
With 22 creep/stress rupture machines operational, and the capability to test designed specimens up to 10-1/8" in length, our Creep and Rupture lab provides the data essential for this evaluation.
Creep testing (creep-rupture, stress-rupture, stress-relaxation) is conducted to determine the deformation (creep) of a material when subjected to a prolonged load at a constant temperature.
- A creep test has the objective of measuring creep and creep rates occurring at stresses usually well below those which would result in fracture.
- In a creep-rupture test, progressive specimen deformation and the time to rupture are measured. In general, deformation during this test is much larger than that developed during a creep test.
- A stress-rupture test is a test in which time to rupture is measured. Deformation measurements are not acquired during this test.
- The stress-relaxation test is similar to the creep test, except the load continually decreases instead of remaining constant. The load is reduced at intervals to maintain a constant strain.
We can conduct the following tests up to 1650°F in temperature and 10,000 lbs in load. Temperature and creep readings are recorded and monitored continuously to ensure accuracy of results. Utilize this data to develop advanced materials fit for application, develop operating limits, estimate service life, develop maintenance schedules and reduce the risk of catastrophic failures of turbine blades, steam pipes and other equipment under high-temperature and stress conditions.
ASTM Test Methods
- ASTM D2990 Compressive Creep and Creep-Rupture of Plastics
- ASTM E139 Creep, Creep-Rupture & Stress Rupture Tests of Metallic Materials
- ASTM E292 Conducting Time-for-Rupture Notch Tension Tests of Materials
- ASTM E328 Stress Relaxation for Materials and Structures.