Papers by Keyword: Temperature Resistance Measurements

Abstract: Mechanical stress-strain hysteresis, temperature and electrical resistance measurements were performed for the microstructure-related characterization of the fatigue behavior and for the fatigue life calculation of metals. The proceeding fatigue damage was evaluated using the change of the load-free electrical resistance, which is strongly influenced by the defect density of the individual material state. A new test procedure was applied for the fatigue assessment under random loading on the basis of cyclic deformation curves, similar to single step loading. A physically based fatigue life calculation “PHYBAL” was developed, which requires only three fatigue tests for the rapid and nevertheless precise calculation of S-N (Woehler) and fatigue life curves.

Abstract: In stress-controlled load increase and single step tests besides the plastic strain amplitude the changes of the temperature and the electrical resistance caused by cyclic plastic deformation were measured. Temperature and resistance measurements don’t require a defined gage length and can be applied also on components even under service loading to ensure economic and safe operation conditions. On the basis of Morrow and Basquin equations a physically based fatigue life calculation “PHYBAL” was developed. This new short-time procedure allows a rapid and precise calculation of Woehler curves with data of one load increase and two single step tests.