scholarly journals A Simple Fatigue Life Prediction Algorithm Using the Modified NASGRO Equation

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Wei Zhang ◽  
Qiang Wang ◽  
Xiaoyang Li ◽  
Jingjing He
Keyword(s):  
Fatigue Life ◽  
Fatigue Limit ◽  
Life Prediction ◽  
Defect Size ◽  
Fatigue Life Prediction ◽  
Prediction Algorithm ◽  
Critical Crack ◽  
Initial Defect ◽  
Effective Threshold ◽  
Crack Growth Model

A simple fatigue life prediction algorithm using the modified NASGRO equation is proposed in this paper. The NASGRO equation is modified by introducing the concept of intrinsic effective threshold stress intensity factor (SIF) rangeΔKeffth. One advantage of the proposed method is that the complex growth behavior analysis of small cracks can be avoided, and then the fatigue life can be calculated by directly integrating the crack growth model from the initial defect size to the critical crack size. The fatigue limit and the intrinsic effective threshold SIF rangeΔKeffthare used to calculate the initial defect size or initial flaw size. The value ofΔKeffthis determined by extrapolating the crack propagation rate curves. Instead of using the fatigue limit determined by the fatigue strength at the specific fatigue life, the fatigue limit is selected based on the horizontal tendency of theS-Ncurve. The calculated fatigue lives are compared to the experimental data of two different alloys. The predictedS-Ncurves agree with the test data well. Besides, the prediction results are compared with that calculated using the FASTRAN code. Results indicate that the proposed life prediction algorithm is simple and efficient.

scholarly journals Fatigue Life Prediction of Austenitic Type 316L Stainless Steel Using ABAQUS

2014 ◽  
Vol 911 ◽  
pp. 459-462
Author(s):  
Khairul Azhar Mohammad ◽  
Mohd Sapuan Salit ◽  
Edi Syams Zainudin ◽  
Nur Ismarubie Zahari ◽  
Ali Aidy
Keyword(s):  
Stainless Steel ◽  
Fatigue Life ◽  
Fatigue Limit ◽  
Life Prediction ◽  
316L Stainless Steel ◽  
Fatigue Life Prediction ◽  
Experimental Comparison ◽  
Element Analysis ◽  
Type 316L ◽  
Type 316L Stainless Steel

This work has carried out on Type 316L stainless steel of hollow bar specimen. The aim of this work is to determine the fatigue life prediction using Finite Element Analysis (FEA). The simulation performed by applied the different stress level to predict the stress of operation to measured life at the measured of operation stress. The simulation emphasis is focused upon the importance of characterize the fatigue limit with compared to data experimental. Comparison of fatigue limit between both simulation and experiment is 150 MPa and 161 MPa, respectively which will provide good agreement in terms of accuracy prediction even various aspects should be taken into account in simulation.

Fatigue life prediction based on an equivalent initial flaw size approach and a new normalized fatigue crack growth model

2016 ◽  
Vol 69 ◽  
pp. 15-28 ◽  
Author(s):  
J.A.F.O. Correia ◽  
S. Blasón ◽  
A.M.P. De Jesus ◽  
A.F. Canteli ◽  
P.M.G.P. Moreira ◽  
...  
Keyword(s):  
Fatigue Crack ◽  
Fatigue Life ◽  
Fatigue Crack Growth ◽  
Crack Growth ◽  
Growth Model ◽  
Life Prediction ◽  
Flaw Size ◽  
Fatigue Life Prediction ◽  
Crack Growth Model

The Fatigue Life Prediction of Pistons Based on the Cumulate Damage

2010 ◽  
Vol 97-101 ◽  
pp. 2654-2657
Author(s):  
Yan Xia Wang ◽  
Yong Qi Liu ◽  
H.Y. Shi
Keyword(s):  
Fatigue Life ◽  
Life Prediction ◽  
Least Squares Method ◽  
Fatigue Behavior ◽  
Fatigue Life Prediction ◽  
Intensity Factors ◽  
Critical Crack ◽  
Critical Crack Length ◽  
Geometry Factor ◽  
Static And Dynamic Analysis

In this study, the FEA static and dynamic analysis for one type of piston are carried out by using software ANSYS to obtained the cranny origin position and stress range value of the dangerous part of the piston, respectively. The critical crack length is analyzed based on the fatigue theory; the stress intensity factors (SIF) are computed, and the expression of the shape geometry factor of the piston is obtained according to the least squares method. An estimated formula of the fatigue life is developed by amending the Paris formula on the basis of studying the fatigue behavior of pistons. Finally, the fatigue cracked life of the piston is calculated using these parameters and the Amending Paris formula.

Fatigue Life Prediction of High-Strength Bolt Subjecting to Torque

2007 ◽  
Vol 345-346 ◽  
pp. 299-302 ◽  
Author(s):  
Young Woo Choi ◽  
Bokkyu Lim ◽  
Sung In Bae
Keyword(s):  
Fatigue Life ◽  
Fatigue Limit ◽  
Life Prediction ◽  
Axial Loading ◽  
High Strength ◽  
Fatigue Life Prediction ◽  
High Strength Bolt ◽  
Calculated Stress ◽  
Concentration Factors ◽  
Stress Concentration Factors

The effect of axial loading resulting from torque on the fatigue life of bolts has been investigated. It was found that the fatigue limit of bolts increased by an amount proportional to the increase in torque. There was a linear relationship between torque and fatigue limit. Using the Shigley method, the prediction of fatigue limit from calculated stress concentration factors was also examined. A good correlation was found between the experimental and predicted fatigue limit. The Shigley method was appropriate for the prediction of fatigue life of bolts.

A Multi-Axial Fatigue Limit Prediction Equation for Metallic Materials

2020 ◽  
Vol 142 (3) ◽  
Author(s):  
Bowen Liu ◽  
Xiangqiao Yan
Keyword(s):  
Fatigue Life ◽  
Prediction Model ◽  
Fatigue Limit ◽  
Life Prediction ◽  
Prediction Equation ◽  
Fatigue Life Prediction ◽  
Stress Effect ◽  
Metallic Materials ◽  
Life Prediction Model ◽  
Axial Fatigue

Abstract Based on the multi-axial fatigue life prediction model presented recently by the authors, in this note, a fatigue limit prediction equation for metallic materials under multi-axial loading is proposed. In the multi-axial fatigue life prediction model, the wildly used von Mises equivalent stress is taken as an equivalent fatigue mechanical quantity, and the multi-axial fatigue life prediction equation has the invariance of mathematical equation form. By applying the multi-axial fatigue life prediction equation without mean stress effect to fatigue limit case, a simple fatigue limit prediction equation can be obtained. By using a large number of experimental data of metallic materials reported in literature, it has been proven that the fatigue limit prediction equation is not only simple in computation but also high in accuracy.

Sign in / Sign up

Export Citation Format

Share Document