Thermal fatigue life analysis and forecast of PBGA solder joints on the flexible PCB based on finite element analysis

This research examines classification approaches for estimating the reliability of structural systems. To validate the accuracy and efficiency of the classification methods, a practical engineering problem; namely, a spider assembly of a washing machine, has been considered. For the spider assembly, fatigue life test, finite element analysis, physical experimentation, and a classification processes are conducted in order to establish the analytical certification of its current design. Specifically, the finite element analysis and fatigue life analysis are performed and their results are validated compared to physical experimental results. The classification process is developed to estimate the probability of failure of the spider assembly in terms of stress and fatigue life. The relationship between the random quantities and structural responses of the spider assembly is established using probabilistic neural network and the support vector machine classifiers. The performance margin of the spider assembly is fully identified based on the estimated failure probability and structural analysis results from the fatigue life analysis and classifications.

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“STRUCTURE ANALYSIS, CONTACT STRESS ANALYSIS AND FATIGUE LIFE ANALYSIS OF SPUR GEAR ASSEMBLY BY USING FEM”

SMART MOVES JOURNAL IJOSCIENCE ◽

10.24113/ijoscience.v4i4.133 ◽

2018 ◽

Vol 4 (4) ◽

pp. 13

Author(s):

Anand Mohan Singh ◽

Megha Bhawsar ◽

Neeraj Kumar Nagayach

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Fatigue Life ◽

Failure Analysis ◽

Contact Stress ◽

Spur Gear ◽

Contact Analysis ◽

Element Analysis ◽

Life Analysis ◽

Fatigue Life Analysis

In this present work a virtual environment has been created to investigate the failure analysis on spur gear assembly in which structural analysis, fatigue failure analysis and contact stress analysis have been performed using finite element method. For this work, a three dimensional cad model has been created and imported to ANSYS workbench for further finite element analysis. Various boundary conditions have been used to perform structural, fatigue failure assessment and contact analysis such as revolute joints is provided with Body Ground connection for 60 rpm for structure analysis, Augmented Lagrange method is set for contact analysis, for fatigue life analysis the fatigue strength factor is used as 0.85 for fully reverse loading and the life of shear stress in cycles and for the contact analysis linear and nonlinear contact are used for both source and target body. It has been observe that contact stress and bending stress not attain their maximum values at the same points, if the contact stress minimize in primary design stage then the failure of gear can minimized by analysis of the problem during the earlier stage of design. It can also be state that by using finite element analysis complex analysis like fatigue and contact analysis can be performed very accurately within a very short time and cost effectively rather than experimental analysis.

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Finite element analysis on the thermal fatigue life of full vs peripheral array packages

Multidiscipline Modeling in Materials and Structures ◽

10.1108/mmms-08-2021-0148 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Mohammad A. Gharaibeh

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Fatigue Life ◽

Thermal Cycling ◽

Thermal Fatigue ◽

Three Dimensional ◽

Element Analysis ◽

Content Type ◽

Thermal Fatigue Life ◽

Thermal Cycling Fatigue

PurposeThis paper aims to examine the thermal cycling fatigue life performance of two-common solder array configurations, full and peripheral, using three-dimensional nonlinear finite element analysis.Design/methodology/approachThe finite element simulations were used to identify the location of the critical solder interconnect, and using Darveaux's model, solder thermal fatigue life was computed.FindingsThe results showed that the solder array type does not significantly influence thermal fatigue life of the interconnect. However, smaller size packages result in improved life by almost 45% compared to larger package designs. Additionally, this paper provided an engineered study on the effect of the number of rows available in a perimeter array component on solder thermal fatigue performance.Originality/valueGeneral design recommendations for reliable electronic assemblies under thermal cycling loaded were offered in this research.

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Impact Characteristics and Fatigue Life Analysis of Multi-Wire Recoil Spring for Guns

Shock and Vibration ◽

10.1155/2020/8853707 ◽

2020 ◽

Vol 2020 ◽

pp. 1-17

Author(s):

Zhifang Wei ◽

Xiaolian Zhang ◽

Yecang Hu ◽

Yangyang Cheng

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Fatigue Life ◽

Life Prediction ◽

Fatigue Life Prediction ◽

Helical Spring ◽

Element Analysis ◽

Life Analysis ◽

Fatigue Life Analysis ◽

The Impact

Recoil spring is a key part in automatic or semi-automatic weapons re-entry mechanism. Because the stranded wire helical spring (SWHS) has longer fatigue life than an ordinary single-wire cylindrically helical spring, it is often used as a recoil spring in various weapons. Due to the lack of in-depth research on the dynamic characteristics of the current multi-wire recoil spring in recoil and re-entry processes, the fatigue life analysis of the current multi-wire recoil spring usually only considers uniform loading and does not consider dynamic impact loads, which cannot meet modern design requirements. Therefore, this paper proposes a research method for fatigue life prediction analysis of multi-wire recoil spring. Firstly, based on the secondary development of UG, a three-wire recoil spring parameterized model for a gun is established. Secondly, ABAQUS is used to carry out a finite element analysis of its dynamic response characteristics under impact, and experimental verification is performed. Then, based on the stress-time history curve of the dangerous position obtained by finite element analysis, the rain flow counting method is used to obtain the fatigue stress spectrum of recoil spring. Finally, according to the Miner fatigue cumulative damage theory, the fatigue life prediction of the recoil spring based on the S-N curve of the material is compared with experimental results. The research results show that the recoil spring has obvious transient characteristics during the impact of the bolt carrier. The impact velocity is far greater than the propagation speed of the stress wave in the recoil spring, which easily causes the spring coils to squeeze each other. The maximum stress occurs at the fixed end of the spring. And the mean fatigue curve (50% survival rate) is used to predict the life of the recoil spring. The calculation result is 8.6% different from the experiment value, which proves that the method has certain reliability.

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Finite element analysis for thermal fatigue life estimation of PBGA solder joints with model validation by experimental data

The Ninth Intersociety Conference on Thermal and Thermomechanical Phenomena In Electronic Systems (IEEE Cat. No.04CH37543) ◽

10.1109/itherm.2004.1318372 ◽

2004 ◽

Cited By ~ 1

Author(s):

S.W.R. Lee

Keyword(s):

Experimental Data ◽

Finite Element Analysis ◽

Finite Element ◽

Fatigue Life ◽

Model Validation ◽

Thermal Fatigue ◽

Element Analysis ◽

Life Estimation ◽

Thermal Fatigue Life ◽

Fatigue Life Estimation

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Fatigue Life Prediction of Girth Gear-Pinion Assembly Used in Kilns by Finite Element Analysis

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.372.292 ◽

2013 ◽

Vol 372 ◽

pp. 292-296 ◽

Cited By ~ 1

Author(s):

K. Annamalai ◽

S. Sathyanarayanan ◽

C.D. Naiju ◽

Mohammed Shejeer

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Fatigue Life ◽

Life Expectancy ◽

Element Analysis ◽

Linear Elastic ◽

Gear Design ◽

Steel Material ◽

Rainflow Cycle Counting ◽

Fatigue Life Analysis

This study is focused on predicting the fatigue life expectancy of Girth gear-pinion assembly used in cement industries. Gear design and modeling was carried out using a CAD package and analysis was done using finite element analysis software, ANSYS. AISI 4135-low alloy steel material properties are considered and linear elastic finite element analysis and fatigue life analysis were carried out. The variable amplitude load is applied to simulate the real time loading of the gear-pinion assembly. Rainflow cycle counting algorithm and Minars linear damage rule is employed to predict the fatigue life. The critical stress and the corresponding deformation are discussed in the results. Finally the life expectancy of the girth gear and pinion assembly is estimated which would be useful for the periodical maintenance of the gear assembly.

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Thermal-mechanical reliability analysis of WLP with fine-pitch copper post bumps

Soldering & Surface Mount Technology ◽

10.1108/ssmt-06-2020-0027 ◽

2020 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Haiyan Sun ◽

Bo Gao ◽

Jicong Zhao

Keyword(s):

Finite Element ◽

Fatigue Life ◽

Thermal Fatigue ◽

Mechanical Performance ◽

Three Dimension ◽

Wafer Level ◽

Element Analysis ◽

Content Type ◽

Cycle Simulation ◽

Thermal Fatigue Life

Purpose This study aims to investigate the several parameters in wafer-level packaging (WLP) to find the most critical factor impacting the thermal fatigue life, such as the height of copper post, the height of solder bump, the thickness of chip. The FEA results indicate the height of solder bumps is the most important factor in the whole structure. Design/methodology/approach The copper post bumps with 65 µm pitch are proposed to investigate the thermal-mechanical performance of WLP. The thermal cycle simulation is used to evaluate the reliability of WLP by using finite element analysis (FEA). Taguchi method is adopted to obtain the sensitivity of parameters of three-dimension finite element model, for an optimized configuration. Findings It can be found that the optimal design has increased thermal fatigue life by 147% compared with the original one. Originality/value It is concluded that the finite element simulation results show outstanding thermal-mechanical performances of the proposed 65 µm pitch copper post bumps of WLP, including low plastic strain, high thermal fatigue life, which are desired for mobile device.

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