Comparison of Equivalent Stress Methods with Critical Plane Approaches for Multiaxial High Cycle Fatigue Assessment

2017-09-07
Engin, Zafer
Çöker, Demirkan
Several equivalent stress methods and more advanced critical plane criteria are compared in terms of their performance in fatigue life estimations under uniaxial and biaxial loadings in which the effect of phase is investigated. For this purpose a MATLAB code is written which transforms the multiaxial cyclic stress state into a uniaxial cyclic stress to use with the equivalent stress based methods. For critical plane approaches the program searches a damage parameter on all material planes. The maximum damage parameter is then compared with a material allowable obtained from uniaxial fatigue tests for life estimation. In addition, various methods for calibration of the material coefficient k and prominent stress history enclosure methods to calculate the shear stress amplitude are also studied for determining their effect on the performance of critical plane approaches. (C) 2017 The Authors. Published by Elsevier B.V.

Suggestions

Implementation of Dirlik’s damage model for the vibration fatigue analysis
Demirel, Gürzap İ.; Kayran, Altan (2019)
Mechanical fatigue is an important phenomenon when the structures are exposed to dynamic, fluctuating loadings. Especially aerospace structures are commonly exposed to random vibration loadings. In this paper, random vibration fatigue is studied both numerically and experimentally. For this purpose, a rectangular cross-section notched beam is designed in order to conduct the vibration fatigue analysis in the frequency domain by the Dirlik's damage model. Aluminum and steel notched beams are prepared in orde...
Analysis of the thermoviscoplastic behavior of [0/90] SCS-6/timetal®21S composites
Çöker, Demirkan; Nicholas, Theodore (1996-01-01)
Micromechanical modeling is used to determine the stresses and strains due to both mechanical and thermal loads in [0/90] titanium matrix composites (TMCs) subjected to cooldown from the processing temperature and subsequent thermomechanical fatigue (TMF) loading conditions. The [0/90] composite is treated as a material system composed of three constituents: fiber and matrix in the [0] ply, and a [90] ply. The [0/90]s layup is modeled by a uniaxial stress rule of mixtures model for the [0] ply and adding a ...
Analysis of the thermomechanical behavior of [0] and [0/90] SCS-6/Timetal 21S composites
Çöker, Demirkan; Nicholas, Theodore (null; 1993-12-01)
Micromechanical modeling is used to determine the stresses and strains due to both mechanical and thermal loads in [0] and [0/90] titanium matrix composites (TMCs) subjected to processing and thermomechanical fatigue (TMF) loading conditions. The concentric cylinder model, due to its simple geometry as well as its capability to capture the three-dimensional aspects of the stress state in a composite, is used to determine the stresses in a unidirectional composite. A representative volume element of the comp...
Comparison of Nondesturctive Stress Measurement Techiques for Determinatuion of Residual Stresses in the Heat Treated Steels
Hizli, Huseyin; Gür, Cemil Hakan (MATERIALS RESEARCH FORUM LLC, 105 SPRINGDALE LN, MILLERSVILLE, PA 17551 USA; 2018-09-14)
Service life and performance of the case-hardened machine parts are greatly dependent on the residual stress state in the surface layers which directly affects the fatigue behavior. Recently, all industrial sectors have been requested for a fast and non-destructive determination of residual stress. This study aims to monitor of the variations in surface residual stress distributions in the carburized 19CrNi5H steels by means of non-destructive and semi-destructive measurement techniques, Magnetic Barkhausen...
Determining the endurance limit of AISI 4340 steels in terms of different statistical approaches
Caliskan, Salim; Gürbüz, Rıza (2021-10-01)
In engineering applications, fatigue phenomenon is a key issue and needs to be analyzed in the beginning of design phase in case of any component exposed to alternating loading on operation otherwise catastrophic fatigue failure may cause. Component can be designed with safe life, fail-safe, and damage tolerant approach based on whether redundant load path and damage sensitive. Before starting analyzing the structure, material allowable data needs to be presented in a reliable way to predict fatigue life of...
Citation Formats
Z. Engin and D. Çöker, “Comparison of Equivalent Stress Methods with Critical Plane Approaches for Multiaxial High Cycle Fatigue Assessment,” 2017, vol. 5, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/39672.