Determination of an HCF criterion by thermal measurements under biaxial cyclic loading

Abstract

A probabilistic two-scale model was recently developed to describe high-cycle fatigue (HCF) properties of steels associated with an identification method of the scatter based on thermal measurements. Up to now, this theoretical framework was used for uniaxial load histories. It is proposed to modify the probabilistic two-scale model to account for the effect of a multiaxial and proportional load histories on HCF properties. This modification consists in the introduction of an equivalent activation stress in the process controlling the plasticity kinetics. Thermal measurements are performed under biaxial tensioncompression load histories to identify and validate an HCF criterion.

A new approach to characterizing and modeling the high cycle fatigue properties of cast materials based on self-heating measurements under cyclic loadings

“…11). An experimental ''iso-temperature surface'' construction is proposed [22,23]. It consists in a series of proportional self-heating tests applied to the same specimen.…”

“…When the temperature variation reaches a given offset, a new path starts with a different loading direction. The offset is chosen to ensure stability of surface shape and to minimize history effects [10,22,23]. For each loading path, the stress amplitude for which the temperature variation reaches the given offset is depicted by a line in the ðr; ffiffiffi 3 p sðr max ÞÞ space (Fig.…”

DIC-aided biaxial fatigue tests of a 304L steel

“…The specimens are loaded by the 4 horizontal actuators (100 KN load capacity, 250 mm stroke range) at a frequency of 10 Hz. Several tests with cyclic loadings have already been performed on cross specimens with this machine ( [8]): they are similar to Low Cycles or High Cycles Fatigue tests in terms of strain amplitudes, nonetheless the applied number of cycles is always below 10 5 . The digital controller 14th International Conference on Experimental Mechanics (Instron 8800) allows each actuator to be controlled independently or in centroid control.…”

Rapid determination of the high cycle fatigue properties of high temperature aeronautical alloys by self-heating measurements

“…It has also been used for different load ratios [7] and extended to multiaxial loadings [8,9]. In all of these cases, the link between self-heating measurements and fatigue properties (at least the mean endurance limit) is established.…”