The specific heat loss combined with the thermoelastic effect for an experimental analysis of the mean stress influence on axial fatigue of stainless steel plain specimens
Journal Title: Frattura ed Integrità Strutturale - Year 2014, Vol 8, Issue 30
Abstract
The energy dissipated to the surroundings as heat in a unit volume of material per cycle, Q, was recently proposed by the authors as fatigue damage index and it was successfully applied to correlate fatigue data obtained by carrying out fully reversed stress- and strain-controlled fatigue tests on AISI 304L stainless steel plain and notched specimens. The use of the Q parameter to analyse the experimental results led to the definition of a scatter band having constant slope from the low- to the high-cycle fatigue regime. In this paper the energy approach is extended to analyse the influence of mean stress on the axial fatigue behaviour of unnotched cold drawn AISI 304L stainless steel bars. In view of this, stress controlled fatigue tests on plain specimens at different load ratios R (R=-1; R=0.1; R=0.5) were carried out. A new energy parameter is defined to account for the mean stress effect, which combines the specific heat loss Q and the relative temperature variation due to the thermoelastic effect corresponding to the achievement of the maximum stress level of the stress cycle. The new two-parameter approach was able to rationalise the mean stress effect observed experimentally. It is worth noting that the results found in the present contribution are meant to be specific for the material and testing condition investigated here.
Authors and Affiliations
G. Meneghetti, M. Ricotta, B. Atzori
Keywords
Related Articles
- EP ID EP158052
- DOI -
- Views 66
- Downloads 0
The research for mechanics stimulation method of nonlinearrandom vibration based on statistical linear theory
Earthquake disasters have brought great harm to people's life safety and economic property. Itseffect on fabric mainly focus on random effects currently, the general pseudo excitation method could solve theineffici...
Influence of dipping time on cracking during bending of hot dip galvanized coatings with Sn and Ti contents
In the last years, the attention to environmental topics led a new approach solution in classical protection techniques, introducing innovative way oriented to optimize different coating properties. Hot-dip galvanizing i...
Structural durability assessment of welded offshore K-nodes by different local design concepts
The structural durability design of complex welded structures should not rely only on one single design method but should apply different methods for assuring the reliability of the assessment. In this context the applic...
High temperature fatigue tests and crack growth in 40CrMoV13.9 notched components
The present paper addresses experimentally the high temperature fatigue of 40CrMoV13.9 steel and the effect of surface roughness on fatigue strength and crack initiation. The 40CrMoV13.9 steel is widely used in d...
Investigation of mixed mode-I/II fracture problems - Part 2: evaluation and development of mixed mode-I/II fracture criteria
In this study, experimental and numerical results of compact tension shear (CTS) specimen and a new specimen type under in-plane mixed mode (Mode-I/II) loading conditions are compared with existing inplane mi...