Transient micromechanical deformation and thermomechanical fatigue damage in AlSi based piston alloys under superimposed high cycle mechanical and low cycle thermal loading

2015 ◽  
Vol 57 (2) ◽  
pp. 155-159 ◽  
Author(s):  
Scott Kenningley ◽  
Roman Morgenstern
Keyword(s):  
Fatigue Damage ◽  
Thermal Loading ◽  
Thermomechanical Fatigue

Visualization of Thermal Fatigue Damage Distribution With Elastic-Plastic FEA

2018 ◽  
Author(s):  
Junya Miura ◽  
Terutaka Fujioka ◽  
Yasuhiro Shindo
Keyword(s):  
Fatigue Damage ◽  
Thermal Fatigue ◽  
Thermal Loading ◽  
304 Stainless Steel ◽  
Element Analysis ◽  
Steel Cylinder ◽  
Elastic Plastic ◽  
Calculation Results ◽  
Type 304 ◽  
Cae System

This paper proposes simplified methods to evaluate fatigue damage in a component subjected to cyclic thermal loading, in order to visualize the distribution of usage factor using a graphical user interface (GUI) incorporated in a widely-used commercial CAE. The objective is to perform the evaluation and visualization using a standard desktop PC. In the previous paper, three simplified methods based on elastic finite-element analysis (FEA) were proposed in place of the method in the procedures employed in ASME Section III Subsection NH. In this paper, the methods have been improved for elastic-plastic FEA. A previously performed thermal fatigue test with a type 304 stainless steel cylinder was simulated. Heat transfer, elastic, and inelastic analyses were conducted. Simultaneously with the analyses performed, the equivalent total strain ranges and fatigue usage factor distributions were calculated using user subroutines developed in this study including three newly proposed simplified and ASME NH-based methods. These distributions can be visualized on a GUI incorporated in a commercial FEA code. The calculation results were consistent with the distribution of cracks observed. In addition, by using these, the analysts can visualize these distributions using their familiar CAE system.

Investigation of Thermal Fatigue Characteristics of Charging Line of RCV in PWR

2017 ◽  
Author(s):  
Naeem Ahmad ◽  
XiangBin Li ◽  
Iftikhar Ahmad ◽  
Nan Li ◽  
Shahroze Ahmed ◽  
...  
Keyword(s):  
Fatigue Damage ◽  
Thermal Fatigue ◽  
Nuclear Power ◽  
Thermal Loading ◽  
Structural Model ◽  
Fatigue Cracks ◽  
Volume Control ◽  
Piping System ◽  
Thermal Transients ◽  
Fatigue Evaluation

Nuclear Power Plant (NPP) components need to tolerate thermal constraints, internal pressure and thermal transients. These thermal transients being repeated again and again can lead to thermal fatigue of the component. It has significant effect on the degradation of the NPP components in long term. Studies of thermal fatigue on different NPP components such as mixing tees and valves have been carried out before but the charging line in the chemical and volume control system (RCV) of the NPP seems to have been ignored for thermal fatigue analysis. Charging Line is the connection from RCV towards Reactor Coolant System (RCP). To enhance the safety of the charging line, thermal fatigue evaluation of piping system was performed using the Fluid Structure Interaction (FSI) analysis. Temperature distributions in the pipes were determined via thermal hydraulic analysis (CFX) and the results were applied to the structural model of the piping system to determine the thermal stress (Transient Structural). Results revealed the location of fatigue cracks. Types of stress were identified that caused the fatigue damage. The CFD analysis enabled us to clarify the role of turbulence with respect to the thermal loading of the structure. The study will provide valuable information for establishing a permanent methodology to help minimize thermal fatigue damage in NPP components.

Thermomechanical fatigue life prediction method for nickel-based superalloy in aeroengine turbine discs under multiaxial loading

2019 ◽  
Vol 28 (9) ◽  
pp. 1344-1366 ◽  
Author(s):  
Fang-Dai Li ◽  
De-Guang Shang ◽  
Cheng-Cheng Zhang ◽  
Xiao-Dong Liu ◽  
Dao-Hang Li ◽  
...  
Keyword(s):  
Fatigue Damage ◽  
Cyclic Deformation ◽  
Deformation Behavior ◽  
Life Prediction ◽  
Prediction Method ◽  
Creep Damage ◽  
Damage Mechanism ◽  
Thermomechanical Fatigue ◽  
Nickel Based Superalloy ◽  
Creep Fatigue

The multiaxial thermomechanical fatigue properties for nickel-based superalloy GH4169 in aeroengine turbine discs are investigated in this paper. Four types of axial–torsional thermomechanical fatigue experiments were performed to identify the cyclic deformation behavior and the damage mechanism. The experimental results showed that the creep damage can be generated under thermally in-phase loading while it can be ignored under thermally out-of-phase loading, and the responded stress increasing phenomenon, that is, non-proportional hardening, can be shown under the mechanically out-of-phase strain loading. Based on the analysis of cyclic deformation behavior and damage mechanism, a life prediction method was proposed for multiaxial thermomechanical fatigue, in which the pure fatigue damage, the creep damage, and the interaction between them were simultaneously considered. The pure fatigue damage can be calculated by the isothermal fatigue parameters corresponding to the temperature without creep; the creep damage can be calculated by the principle of subdivision, and the creep–fatigue interaction can be determined by creep damage, fatigue damage, and an interaction coefficient which is used to reflect the creep–fatigue interaction strength. The predicted results showed that the proposed method is reasonable.

Thermomechanical fatigue damage evolution in SAC solder joints

2007 ◽  
Vol 445-446 ◽  
pp. 73-85 ◽  
Author(s):  
M.A. Matin ◽  
W.P. Vellinga ◽  
M.G.D. Geers
Keyword(s):  
Fatigue Damage ◽  
Damage Evolution ◽  
Solder Joints ◽  
Thermomechanical Fatigue ◽  
Sac Solder

A multiresolution investigation on fatigue damage of aluminum alloys at micrometer level

2017 ◽  
Vol 26 (2) ◽  
pp. 192-209 ◽  
Author(s):  
H Chen ◽  
X Shi ◽  
Q He ◽  
JH Mao ◽  
Y Liu ◽  
...  
Keyword(s):  
Fatigue Damage ◽  
Thermal Loading ◽  
Low Cycle Fatigue ◽  
Transformation Process ◽  
Lessons Learned ◽  
Future Research ◽  
Element Analysis ◽  
Young’S Moduli ◽  
Macro Scale ◽  
Fatigue Damage Analysis

Fatigue damage is a form of material degradation under repeated mechanical and/or thermal loading. A new multiresolution fatigue damage analysis is formulated and used to estimate low-cycle fatigue damage. The progressive fatigue damage is measured based on the X-ray computed tomography. Then, the measured microcracks and microvoids are transformed to mesoscale and macro-scale damage variables. The entire transformation process is achieved analytically by means of 3D finite element analysis and specially formulated super representative volume elements. The estimated macro-scale damage variables in terms of effective Young’s moduli are compared with those measured experimentally and found to be in agreement. Some lessons learned in this study are provided for the direction of future research.

Thermomechanical fatigue damage modeling and material parameter calibration for thin film metallizations

2021 ◽  
pp. 106627
Author(s):  
Paul Hoffmann ◽  
Sebastian Moser ◽  
Corinna Kofler ◽  
Michael Nelhiebel ◽  
Daniel Tscharnuter ◽  
...  
Keyword(s):  
Thin Film ◽  
Fatigue Damage ◽  
Material Parameter ◽  
Thermomechanical Fatigue ◽  
Damage Modeling ◽  
Parameter Calibration
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