Probabilistic fatigue damage estimation of embedded electronic solder joints under random vibration

This paper presents a numerical investigation of the probabilistic approach in estimating the reliability of wire bonding, and develops a reliability-based design optimization Methodology (RBDO) for microelectronic device structures. The objective of the RBDO method is to design structures which should be both economical and reliable where the solution reduces the structural weight in uncritical regions. It does not only provide an improved design, but also a higher level of confidence in the design. The Finite element simulation model intends to analyze the sequence of the failure events in power microelectronic devices. This numerical model is used to estimate the probability of failure of power module regarding the wire bonding connection. However, due to time-consuming of the multiphysics finite element simulation, a response surface method is used to approximate the response output of the limit state, in this way the reliability analysis is performed directly to the response surface by using the First and the Second Order Reliability Methods FORM/SORM. Subsequently the reliability analysis is integrated in the optimization process to improve the performance and reliability of structural design of wire bonding. The sequential RBDO algorithm is used to solve this problem and to find the best structural designs which realize the best compromise between cost and safety.

Reliability based design optimization of wire bonding in power microelectronic devices

Design optimization of structural and multidisciplinary systems under uncertainty has been an active area of research due to its evident advantages over deterministic design optimization. In deterministic design optimization, the uncertainties of a structural or multidisciplinary system are taken into account by using safety factors specified in the regulations or design codes. This uncertainty treatment is a subjective and indirect way of dealing with uncertainty. On the other hand, design under uncertainty approaches provide an objective and direct way of dealing with uncertainty. This paper provides a review of the uncertainty treatment practices in design optimization of structural and multidisciplinary systems under uncertainties. To this end, the activities in uncertainty modeling are first reviewed, where theories and methods on uncertainty categorization (or classification), uncertainty handling (or management), and uncertainty characterization are discussed. Second, the tools and techniques developed and used for uncertainty modeling and propagation are discussed under the broad two classes of probabilistic and non-probabilistic approaches. Third, various design optimization methods under uncertainty which incorporate all the techniques covered in uncertainty modeling and analysis are reviewed. In addition to these in-depth reviews on uncertainty modeling, uncertainty analysis, and design optimization under uncertainty, some real-life engineering applications and benchmark test examples are provided in this paper so that readers can develop an appreciation on where and how the discussed techniques can be applied and how to compare them. Finally, concluding remarks are provided, and areas for future research are suggested.

Modeling, analysis, and optimization under uncertainties: a review

The purpose of the Reliability-Based Design Optimization (RBDO) is to find the best compromise between safety and cost. Therefore, several methods, such as the Hybrid Method (HM) and the Optimum Safety Factor (OSF) method, are developed to achieve this purpose. However, these methods have been applied only on static cases and some special dynamic ones. But, in real mechanical applications, structures are subject to random vibrations and these vibrations can cause a fatigue damage. So, in this paper, we propose an extension of these methods in the case of structures under random vibrations and then demonstrate their efficiency. Also, a Robust Hybrid Method (RHM) is then developed to overcome the difficulties of the classical one. A numerical application is then used to present the advantages of the modified hybrid method for treating problem of structures subject to random vibration considering fatigue damage.

Reliability Based Design Optimization for Multiaxial Fatigue Damage Analysis Using Robust Hybrid Method

In this article, a dynamic analysis of an offshore wind turbine (OWT) considering soil structure interaction (SSI) is performed. The design of these highly expensive structures tends to find the be...

A modified hybrid method for a reliability-based design optimization applied to an offshore wind turbine

In the reliability-based design optimization (RBDO) model, the mean values of uncertain variables are usually applied as design variables, and the cost is optimized subject to prescribed probabilis...

Reliability-based design optimization with frequency constraints using a new safest point approach

The need of progress in engineering designs especially for aerospace structure is nowadays becoming a major industry request. The objectives of this work are to quantify the influence of material and operational uncertainties on the performance of the aerodynamic behavior of an Aircraft Wing, and to give a description of the most commonly used methods for reliability based design optimization (RBDO) to point out the advantages of the application of this method in the design process. A new method is proposed, called Safest Point (SP) that can efficiently give the reliability-based optimum solution for freely vibrating structures with and without fluid flow.

RBDO analysis of the aircraft wing based aerodynamic behavior

http://ieeexplore.ieee.org/iel7/6776777/6776778/06776794.pdf

Robustness study of solder joints of different compositions by using Stochastic Finite Element Modeling

In this paper, we present a new method based on Optimal Safety Factors (OSF) in the context of the Reliabil- ity-Based Design Optimization (RBDO) analysis of ultrasonic motors with traveling wave taking into account the contact between the different components (stator and rotor). We will underline also the different methods of the RBDO analysis and we highlight the advantage of our approach based on OSF. Numerical results are given to illustrate the proposed me- thod.

/pdf/optimization-safety-factors-to-study-an-ultrasonic-motor-r14oo99e36.pdf

Abderahman Makhloufi

Papers

Reliability based design optimization of wire bonding in power microelectronic devices

Reliability-based design optimization with frequency constraints using a new safest point approach

RBDO analysis of the aircraft wing based aerodynamic behavior

Robustness study of solder joints of different compositions by using Stochastic Finite Element Modeling

Optimization Safety Factors to Study an Ultrasonic Motor