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Diversified trading networks have recently drawn a great deal of attention. In the process, the importance of diversity has perhaps been overemphasized. Using the trade in port wine from Portugal to Britain as an example, this essay attempts to show how a market once dominated by general, diversified traders was taken over by dedicated specialists whose success might almost be measured by the degree to which they rejected diversification to form a dedicated “commodity chain.” The essay suggests that this strategy was better able to handle matters of quality and the specialized knowledge that port wine required. The essay also highlights the question of power in such a chain. Endemic commodity-chain struggles are clearest in the vertical brand war that broke out in the nineteenth century, which, by concentrating power, marked the final stage in the transformation of the trade from network to vertical integration.

Enclosed print heads have recently been developed as an improvement on the traditional squeegee methods for solder paste printing. They offer the opportunity of widening the printing process window and reducing process waste. Consequently, this work was undertaken to evaluate some aspects of enclosed print head printing, and it has been shown to be a robust process. A number of performance factors were established: with increased humidity the paste degradation was limited due to its sealed paste reservoir; the system also permitted successful intermittent printing over a 5 day period; printing is much more tolerant to distorted substrates than some squeegee blades, and hence improves printing on non‐planar surfaces; significant reduction in paste wastage occurs, since paste ageing is reduced.

This conceptual paper argues that the emergence of Internet commerce is presenting a significant challenge to traditional internationalization explanations. Given rapid accessibility to customers and suppliers around the world, businesses appear to be turning towards networks of cooperation rather than external control structures. International supply chain management is proposed as a process of internationalization representing the implementation of a global uncertainty‐driven new network orientation. A network orientation is proposed to encourage more integrated levels of I‐commerce adoption which, in turn, further strengthens the relationship between a network orientation and its implementation. A number of propositions are presented along with a discussion of future research issues.

This work sets out to characterise the protective properties of conformal coatings and how they degrade.

The approach dosed several commercial coatings with two different contaminants, a synthetic generic flux mixture of dibasic acids in both a solvent‐ and water‐based carrier, and sodium chloride. The protective properties were monitored using three complementary techniques: surface insulation resistance measurements, sequential electrochemical reduction analysis, and diffusion measurements.

The experimental approach was verified and the SIR measurements were shown to be the most valuable. Coatings offered varying levels of resistance to the contaminants, with the silicone coating being the most resistant. The flux variants generally proved more harmful to the coatings, suggesting that flux diffusion through the coating exceeded that of NaCl and hence led to greater electrochemical corrosion. Flux transmission through the coatings was verified by the diffusion measurements.

The project only investigated a limited number of contaminates on simple single sided boards. Future work will investigate coverage effects and a wider range of contaminants.

The work shows that coatings can allow diffusion of contaminates, particularly organics, which can lead to corrosion. The test methodology described here can be used to characterise coating susceptibility.

This work starts to develop for the first time a test methodology to characterise the protective properties of conformal coatings, and shows that flux, and hence other similar organic contaminants, may represent a protection challenge for some coating chemistries.

The purpose of this work is to undertake a comparison of accelerated test regimes for assessing the reliability of solder joints, in particular those made using lead‐free solders.

Identical samples of 1206, 0805 and 0603 resistors were subjected to six different cycling regimes to investigate the effect of thermal excursions, ramp rates and temperature dwells.

The most damage to joints was found to be caused by thermal cycling between −55 and 125°C, with a 10°C/min ramp rate and 5 min dwells. Large thermal excursions were shown to give faster results without compromising the failure mode.

Similar degrees of damage in the lead‐free solder joints were experienced from thermal shock regimes with ramp rates in excess of 50°C/min. However, these regimes, although faster to undertake, appeared to cause different crack propagation modes than observed with the thermal cycling regimes. However, these differences may be small and thermal shock testing may still be used to differentiate between, or enable ranking of, the effects of changes to materials or processes on the reliability of the solder joints. Hence, it is envisaged that if a wide range of conditions are to be tested a first sift can be completed using thermal shock, with the final work using typical thermal cycling conditions.

The difference between the SAC (95.5Sn3.8Ag0.7Cu) and SnAg (96.5Sn3.5Ag) solder alloy results across all types of cycles showed very little difference in the rates of joint degradation.

This paper compares relative reliability (remaining shear strength) of three chip components soldered with two lead‐free alloys based on various thermal cycling conditions.

The purpose of this paper is to discuss a new method to measure the fatigue of single solder joints in shear, and hence calculate the joint strain energy density in each fatigue cycle.

There has been a step change in the requirement to characterise solder joint reliability with the number of new alloys introduced as a result of the recent RoHS legislation. Experimental testing for every configuration is expensive and time consuming, and hence modelling has become more attractive. The accuracy of modelling predictions is limited by the accuracy of the materials data. The data for these new alloys must reflect the miniaturisation of electronics and that solder joints are loaded in shear, two aspects not well reflected in the existing SnPb data. The approach here has been to develop an instrument interconnect properties test machine, where the strain and stress can be measured directly for small solder volumes and in shear. A four‐point measurement system for resistance monitoring has also been evaluated and found to correlate well with load decreases recorded during fatigue testing of solders, and hence provide a method to calculate the crack area.

The experiments have recorded the stress strain behaviour during isothermal fatigue. The developing crack area has been measured using an electrical resistance technique and has been used to correct the stress values. Using the corrected stress the strain energy data can be calculated.

The work has been limited to a single alloy and a single joint configuration, with time these will be broadened and the experimental fatigue parameters extended.

These measurements will provide a route for calibrating the finite element models. A databank of material properties could be built up for alloys used in a range of configurations. This would help support and widen the use of modelling to predict fatigue life.

There is an increasing awareness of the importance of measuring microelectronic solder joint fatigue properties. There are a number of approaches being pursued, but the work at NPL is important in allowing the experiment to be controlled by either stress, strain or temperature, and with the added ability to measure crack area. This uniquely enables the measurement directly of the strain energy density during a fatigue experiment.

SIR testing is in practice carried out under a wider range of experimental conditions than those detailed in standards. The work presented here explores some of the issues when using a range of fluxes with various processing conditions and also examines the influence of substrate finish, test bias and the reflow process. These results clearly show that care must be exercised when using different test set‐ups, and when extrapolating between testing and use conditions. In particular the use of a 50V test bias voltage can produce anomalous results when compared to a 5V use environment.

Within the new public management (NPM) context, this paper aims to examine the inclusion of equity issues in pricing policy development and implementation in the water industry in Australia.

A review of literature relevant to the pricing of water shows equity issues have four dimensions which tend to be, at best, only implicitly considered. An empirical illustration employing a transaction cost framework is provided of a case in which change in pricing mechanisms was strongly suggested.

An equity paradox emerges as an explanation of why 63.7 per cent of Queensland urban water entities chose not to adopt the user-pays pricing mechanism for water. This suggests that the balance between “equity” and “efficiency” continues to be required in policy development for water pricing. Equity of access and that of distribution continue to be significant factors. As well, equity of interest and of return must be considered, especially under a user-pays pricing mechanism.

In respect of NPM considerations, it is argued that consideration of the four dimensions of equity in the implementation of a water pricing policy will resolve contradictions with, and paradoxes met in dealing with efficiency.

The argument used in the paper is interdisciplinary. References and terms used include those which are social, economic, and environmental from an accounting and management perspective.

The printing process is the most critical step in surface mount assembly. To control and monitor printing, complex instrumentation is available for measuring the print consistency. This paper describes a novel robust method, which introduces critical variables defining print quality. Conventional measurement methods include only the volume and average height of solder paste. The limitations of using just these parameters are discussed and a new method is introduced. In our novel approach, the matrix is levelled first to take account of any tilt in the plane of the substrate surface. Then pseudo‐virtual object parameters are calculated. Major attributes of the proposed measurement method is its insensitivity to both the specific location of the printed deposit and the location of a specific defect. This algorithm, coupled with variables defined in the analysis package, delivers a new and flexible approach to the printed media.

The surface insulation resistance (SIR) test has traditionally been performed by taking measurements at certain points during a seven‐day test under well established environmental conditions. The work reported here explores the influence of test temperature and humidity when using a typical resin flux, a weak organic flux and glycol based fluxes when sampling SIR patterns every ten minutes. Results indicate that some fluxes are very sensitive to the test temperature, with volatilisation of flux residues an important issue. The frequent monitoring of the results also permitted the detection of dendrites during the SIR test. The results clearly show the importance of selecting the correct testing conditions and the benefit of frequent monitoring.