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Tin and solder coatings interact with substrates commonly used in the electronics industry to produce layers of intermetallic compounds at temperatures above and below the melting point of the coatings. Observations on the rates of compound growth at room temperature for durations of up to 12 years are reported and related to the published results for shorter times at higher temperatures. Recent results concerning the effect of intermatallic compound growth on the solderability of coatings and on the strength of soldered joints are presented. In both cases it is apparent that retarding the rate of compound growth could be useful and the use of barrier layers for this purpose is considered.

On 20 April ISHM‐Benelux held its 1988 Spring meeting at the Grand Hotel Heerlen. This meeting was totally devoted to implantable devices, in particular to the technologies used for these high reliability, extremely demanding devices. For this meeting ISHM‐Benelux was the guest of the Kerkrade facility of Medtronic. Medtronic (headquartered in Minneapolis, USA) is the world's leading manufacturer of implantable electronic devices. Apart from the assembly of pacemakers and heart‐wires, the Kerkrade facility acts as a manufacturing technology centre for Medtronic's European facilities.

The kinetics of wetting were studied on several different prepared surfaces of copper (Cu) to simulate the microstructure observed in pre‐tinned Cu‐clad printed circuit boards. The results illustrate the effectiveness of pre‐tinning in maintaining the solderability of Cu surfaces. Pre‐tinning with Pb‐rich solder (95Pb‐5Sn) is particularly effective since solderability is preserved even after a relatively long ageing treatment. On the other hand, pre‐tinning with eutectic solder risks the loss of solderability during ageing or baking due to surface exposure of an ε‐phase intermetallic with poor wetting properties. The results also confirm the presence of carbon in pre‐tinned specimens due to the use of flux. The effect of carbon on solderability is not yet known.

In an electronic manufacturing environment, rework of pin‐in‐hole components on printed circuit boards is an essential process. Rework enhances product yield and through‐put efficiency by allowing device repair to occur quickly and at significantly reduced costs in comparison with complete board reconstruction. However, current rework techniques are not without their shortcomings, most notably enhanced dissolution of copper in plated‐through holes. This paper discusses a new methodology using polymer films as barrier layers, resulting in negligible plated‐through‐hole copper dissolution when conventional rework technologies are practised.

The introduction of high density surface mount technology may lead to a number of metallurgical problems. This paper considers two aspects which are currently being actively discussed. Firstly, incompatibility in expansion properties of the materials used and severe thermal cycling may induce creep and fatigue stresses on soldered joints, and the merits of different alloys are considered. Secondly, the necessary thermal treatments such as burn‐in and elevated service temperature can lead to intermetallic compound layer growth between the solder and the metallised layer on components which may be considered a potential source of joint strength reduction. Mention is also made of the different visual appearance of joints to chip components compared with conventional soldered joints.

The paper presents the results of extensive studies on circuit board solderability comparing wetting balance and IPC test methods through performance in vapour phase and wave soldering operations. The effects on solderability of key parameters are examined and compared with storage times of one year, and accelerated ageing using damp heat, dry heat and steam oxygen. An evaluation is made of tin‐lead alloys from 40/60 to 70/30 in solder coating thicknesses from 0·1 to 1·0 mil.

The role of intermetallics in soldered joints is ambivalent. They are an essential part of joints to common basis materials and at low levels they have a strengthening effect on solder alloys. At higher levels, however, it is well known that they can cause joint embrittlement. In this paper three aspects of their role have been studied: the microstructure of intermetallic containing solder alloys, the effects of soldering parameters on the quantity of intermetallic formed and, finally, the rates of growth of intermetallic compounds in the solid state. The results suggest that alloys which are pre‐doped with copper tend to form slightly more interfacial intermetallic during soldering than those which are not. In the solid state the rates of growth appear to be a function of the melting point of the alloy, with the higher melting point lead‐free alloys exhibiting lower rates than lower melting point alloys such as 63Sn37Pb (183∞C) or 42Sn58Bi (138∞C).

This paper aims to describe and document the application of commonly utilized solder joint failure analysis techniques to lead‐free solder joints.

Traditional failure analysis techniques, including visual inspection, X‐ray radiography, mechanical strength testing, dye and pry, metallography, microscopy and photomicrography, are reviewed. These techniques are demonstrated as applied to lead‐free and tin lead solder joints. Common failure modes observed in lead‐free and tin lead solder joints are described and compared.

It is shown that the traditional failure analysis techniques previously utilized for tin lead solder joints are widely applicable to the analysis of lead‐free solder joints. The changes required to effectively apply these techniques to the analysis of lead‐free solder joints are described.

This paper will be instrumental to the process, quality, reliability and failure analysis engineering disciplines in furthering understanding of the application of failure analysis techniques of both tin lead and lead‐free solder joints.

The present chapter puts one perspective center stage and looks at the relationship between TSC and its manifestation in individuals. More specifically, we are concerned with the relationship between processes of attitude formation and attitude change. The concept of attitudes is one out of several psychological constructs which are known to have mediating influence on actual behavior. Thus, it is a possible starting point to positively influence behavior in road traffic toward higher levels of (commitment to) safety. Understanding how safety culture is internalized by individuals and how it shapes safe conduct shall be theoretically described and practically exemplified to show how this approach can become useful and relevant for practitioners in the field of road safety.

The argument is developed in three parts. In the first part, Herbert Kelman’s (1958) conceptual scheme of three stages of attitude change is presented in which the levels of compliance, identification, and internalization of values are distinguished. In the second part, it is argued that these different levels of value integration correspond with three different kinds of psychological theories which address the relationship between attitudes and deliberately conducted behavior (action). It is a well-known fact in the science of human action that there is no direct relationship between attitudes, decision making, and action. Using Kelman’s three levels of value internalization as a scheme of reference, the conditions under which persons act in line with their attitudes can be conceptualized more precisely. From a normative point of view, it is argued that persons who align their actions and attitudes with reference to socially appreciated values are said to be elaborated. They orient their conduct by an ethos of safety to which they feel committed and they are able to interact in mindful ways. We discuss some of the basic constructs at each level and underpin their importance with reference to behavioral change toward higher levels of safety with empirical findings that have been published. In a third part, we present our findings in a summarizing table and suggest a list of factors and themes which mainly correspond to one of the three stages of attitudinal change and value internalization. Finally, we outline some examples of how traffic safety interventions can be conceptualized at these different levels.

The members of the chapter at the annual meeting held on 27 November 1992 in Brno decided not to split after the separation of Czechoslovakia. It was suggested to organise a larger chapter from the Central European States to provide greater co‐operation and better functioning of the smaller chapters. A new name for the chapter was proposed — Central European Chapter (CEC) — to express neutrality and to point out that the chapter is open to other neighbouring chapters and to new members from the states where no national chapter yet exists.