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The purpose of this paper is to evaluate modeling of the reliability characteristics of the copper (Cu) used in plated through holes (PTHs) for electrical connections across printed circuit boards (PCBs).

Assessments of the Cu damage in the first three reflow cycles are performed using finite element analysis. A two‐dimensional axi‐symmetric model of a PTH on a laminate board is validated against a three‐dimensional full model and test cases. Stress and strain measurements in the inner ring of the PTH are obtained in numerical simulations.

Loads applied after the reflow cycles contribute to subsequent mechanical disconnects. Reliability assessments relying on undamaged circuits are less accurate than estimates incorporating Cu damage following three reflow cycles.

In order to increase the accuracy of PCB reliability predictions significantly, prior‐to‐use damage should be calculated. In this paper, a modification to the reliability analysis is proposed.

This paper studies a production planning problem in printed circuit board (PCB) assembly. A PCB assembly line has several non‐identical placement machines, so the placement times by different machines are various to the same type of components. Several mathematical models are formulated in order to obtain a best assignment of components to machines with the objective of minimizing the cycle time to have the best line throughput. Moreover, the data structures of the models are analyzed and compared with other similar models to search a good available algorithm. Finally, a numerical example is provided to illustrate these models and is solved by a computer package.

Flextronic Ltd, a UK leader in the manufacture and assembly of flexible circuits, have appointed Rob Lomer to the post of Quality Manager for both of their Chichester sites. Mr Lomer has extensive quality management experience in the electronics environment, having introduced total quality management initiatives as well as statistical process control in previous posts. He is also intimately familiar with BS 7000/BS 5750 and ISO 9000/ EN 2900 in the USA as well as in the UK and mainland Europe.

Solder materials are used to provide a connection between electronic components and printed circuit boards (PCBs) using either the reflow or wave soldering process. As a board assembly passes through a reflow furnace the solder (initially in the form of solder paste) melts, reflows, then solidifies, and finally deforms between the chip and board. A number of defects may occur during this process such as flux entrapment, void formation, and cracking of the joint, chip or board. These defects are a serious concern to industry, especially with trends towards increasing component miniaturisation and smaller pitch sizes. This paper presents a modelling methodology for predicting solder joint shape, solidification, and deformation (stress) during the assembly process.

The simulated temperature profile of the printed circuit board assembly (PCBA) during reflow soldering process deviates from the actual profile. To reduce this relative deviation, a new strategy based on the Kriging response surface and the Multi-Objective Genetic Algorithm (MOGA) optimizing method is proposed.

The simulated temperature profile of the PCBA during reflow soldering process deviates from the actual profile. To reduce this relative deviation, a new strategy based on the Kriging response surface and the MOGA optimizing method is proposed.

Several critical influencing parameters such as temperature and the convective heat transfer coefficient of the specific temperature zones are selected as the correction parameters. The hyper Latins sampling method is implemented to distribute the design points, and the Kriging response surface model of the soldering process is constructed. The updated model is achieved and validated by the test. The relative derivation is reduced from the initial value of 43.4%–11.8% in terms of the time above the liquidus line.

A new strategy based on the Kriging response surface and the MOGA optimizing method is proposed.

The purpose of this study is to investigate heat transfer and deformation of flexible printed circuit board (FPCB) under thermal and flow effects by using fluid structure interaction. This study simulate the electronic cooling process when electronic devices are generating heat during operation at FPCB under force convection.

The thermal and flow effects on FPCB with attached ball grid array (BGA) packages have been investigated in the simulation. Effects of Reynolds number (Re), number of BGA packages attached, power supplied to the BGA packages and size of FPCB were studied. The responses in the present study are the deflection/length of FPCB (δ/L) and Nusselt number (Nu).

It is important to consider both thermal and flow effects at the same time for understanding the characteristic of FPCB attached with BGA under operating condition. Empirical correlation equations of Re, Prandtl number (Pr), δ/L and Nu have been established, in which the highest effect is of Re, followed by Pr and δ/L. The δ/L and Nu¯ were found to be significantly affected by most of the parametric factors.

This study provides a better understanding of the process control in FPCB assembly.

This study provides fundamental guidelines and references for the thermal coupling modelling to address reliability issues in FPCB design. It also increases the understanding of FPCB and BGA joint issues to achieve high reliability in microelectronic design.

A new Sensitek range of automatic continuity test systems has just been announced by Systran Donner Ltd. The company has also introduced the new Testronics 100 series of automatic continuity analysers.

This paper focuses on gender and technology in the organization. It considers some of the difficulties experienced by women building careers as professional engineers in a high technology industrial organization in England. Using career history data from 15 women engineers, the paper examines the experience of gender in the organization and the attempts by the women to manage gender relations. The paper argues that the difficulties were not associated with the culture of engineering work itself: the women could manage the technology. The problems lay rather in the organization itself. The gendered expectations and processes within the organization constituted the real dilemma for women’s careers.

The paper aims to present a modeling method for multi‐layer, multi‐material printed circuit boards (PCBs) in both micro‐structure and board levels.

The method incorporates a multilayer finite element model that is established in two parts: the first part is an elasto‐plastic damaging model, which is presented to model metallic plies in the multi‐layer PCBs, while the second is a bi‐phase model for glass‐fiber/epoxy‐resin composite ply with fiber/matrix structure.

Numerous composite parts and complex material properties of multi‐layer PCBs complicate the reliability of the simulation. Therefore, the board level simulation and the micro‐structure modeling cannot be performed at the same time. A multi‐layer FEM code can solve this problem: with the use of bi‐phase and elasto‐plastic plies in this code, the micro‐structure and board‐level modeling for multi‐layer PCBs can be incorporated.

With the implementation of a virtual boundary method, the current multi‐layer model can be combined with the unit‐cell modeling method to perform detailed analysis at the micro‐structure level.

This paper presents a method for multi‐layer PCB modeling at both the micro‐structure and board levels. It provides a way to individually design the fabric types and the properties of glass fibers, epoxy resin, and copper foil in PCBs, to meet specific reliability requirements. With the proposed modeling, the static and shock responses of optimized PCBs can be analyzed with less computation.