The standard “E606/E606M-21 Standard test method for stress-controlled fatigue testing” developed by the American Society for Testing and Materials (ASTM) describes a test method for determining the fatigue properties of nominally homogeneous materials using test specimens subjected to uniaxial forces. This standard is designed as a guide for fatigue testing performed to support activities such as materials research and development, mechanical design, process and quality control, product performance, and failure analysis. Although this test method is primarily designed for stress-controlled fatigue testing, some sections may provide useful information for force-controlled or stress-controlled testing.
The use of this test method is limited to samples and does not extend to testing of full-scale components, structures, or consumer products.
This test method is valid for temperatures and strain rates at which the magnitudes of the time-dependent inelastic stresses are of the same order of magnitude as or less than the magnitudes of the time-dependent inelastic stresses. No restrictions are placed on environmental factors such as temperature, pressure, humidity, ambient and others, provided that they are controlled throughout the test, do not cause dimensional loss or change with time and are detailed in the data report.
The term inelastic is used here to refer to all inelastic stresses. The term plastic is used here to refer only to the time-independent (i.e. non-creep) component of the inelastic stress. To determine a truly time-independent stress, the force would have to be applied instantaneously, but this is not possible. A useful engineering estimate of the time-independent stress can be obtained when the stress ratio exceeds some value.
This test method is limited to testing of uniform gauge section test specimens subjected to axial forces. Testing is limited to stress-controlled cycling. The test method is applicable to hourglass specimens, but the user is cautioned about uncertainties in data analysis and interpretation. Testing is primarily conducted under constant amplitude cycling and may include holding periods interspersed with repeated intervals. The test method may be adapted to guide testing for more general situations where stress or temperature may vary according to application-specific histories. In such cases, data analysis may not follow this test method.
For the purposes of this standard, the following terms and definitions apply:
Stress-controlled fatigue is a phenomenon affected by the same variables that affect force-controlled fatigue. The nature of stress-controlled fatigue places different requirements on fatigue testing methods. In particular, the cyclic total stress must be measured and the cyclic plastic strain determined. Furthermore, since either of these stresses is typically used to determine cyclic limits, the total stress is usually controlled throughout the cycle. The uniqueness of this test method and the results it yields are the determination of cyclic stresses and strains at any time during the tests. Differences in stress histories other than constant amplitude will alter fatigue life compared to constant amplitude results (e.g., periodic overstresses and block or spectrum histories).
Similarly, the presence of non-zero mean stresses and changing environmental conditions may alter fatigue life compared to constant amplitude, fully inverse fatigue tests. Caution should be exercised when analyzing and interpreting data for such conditions. In the case of variable amplitude or spectrum stress histories, cycle counting may be performed in accordance with “ASTM E1049-85(2023) Standard Practices for Cycle Counting in Fatigue Analysis”.
Among the numerous testing, measurement, analysis and evaluation studies that our organization has provided for businesses in various sectors, it also provides testing services defined in the “E606/E606M-21 Standard test method for stress-controlled fatigue testing” standard with its trained and expert staff and advanced technological equipment.
To get an appointment, to get more detailed information or to request an evaluation, you can ask us to fill in our form and reach you.
