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Arising from discussions at the International Institute of Welding Solder Paste Committee, the influences of a number of testing variables on the tack strength of solder pastes have been examined using the load cell system on a Meniscograph Solderability Tester. As a result, a standard method of testing has been proposed.

This chapter explores two business and innovation strategies to increase sustainability in a small-medium enterprise. The two strategies, one addressing the improved sustainability of an existing product line and the other addressing the development and implementation of a new product line, employ different supply chain sustainable practices and utilize different dynamic capabilities.

The chapter describes how sustainable supply chain management practices, sustainable new product development processes, and theories of dynamic capabilities interact to support a sustainable and differentiated strategy in the Alcass organization.

The models of sustainable supply chain management and sustainable new product development are applied to “more sustainable” products and “new sustainable” products, by raising different relevant practices as well as different supporting dynamic capabilities.

Quality Control and/or Assurance and similar phrases are in common use but can have different meanings, depending on the type of product involved and on economic considerations. It is proposed that, from the soldering point of view, component design and solderability must be as good as possible and must be regularly checked. There must be adequate control over every aspect of the soldering process, and inspection of the completed assembly must be meaningful with realistic accept/reject levels decided upon at the outset. Having established a complete production scheme incorporating quality checking, it is proposed that no alterations should be made without full consultation and collaboration with all the personnel concerned.

Thermal cycling tests for surface mounted components are usually taken around a mean temperature of approximately 35°C (e.g., −55°C to +125°C; −40°C to +110°C). To test the effect of different maximum temperatures thermal cycling tests using a lower temperature of −55°C have been conducted with alumina/thick film ‘zero‐ohm’ jumper chips with nickel barriers. These are connected in series chains and wave soldered on to FR‐4 test coupons (128 chips/coupon). The test regimes used were −55°C to +5°C; +65°C; +95°C, +110°C and +125°C. Resistance changes before and after cycling were observed at room temperature. After 100 cycles changes of approximately +200 mΩ were observed against a total resistance of 5·5 Ω. However, more detailed examination showed that a top temperature of +95°C gives optimum results with a total change over 100 cycles of +4·9%.

In the production of printed circuit assemblies, the demand for higher reliability levels has increased over the years. In order to achieve a high level of soldering quality, it is essential that solderability is built into the system at all stages and various factors must be taken into account. In the first section of this paper some of these factors are discussed. The various solderable coalings that are available are reviewed, some of the problems that can be encountered are illustrated and the effects of impurities in solders discussed. In the second part of the paper, the use of circuit boards having fused tin/lead coatings is discussed from the solderability point of view.

Bryan Pledger, Chairman of the IMF Printed Circuit Group, chaired this meeting, held in London on 26 September, and introduced the panel of speakers, well‐known nationally and internationally, and specialists in the field of surface mounting.

This paper presents a viscoelastic model for analysing the mechanical behaviour of SnPb solders which has been developed by combining grain boundary slip with viscoelasticity theory. On the basis of the model, and by using Boltzmann's integral constitutive equation of viscoelasticity, the mechanical behaviour (i.e., the relationships between stress (load) and strain (displacement)) of SnPb solders for one‐dimensional shearing deformation has been investigated and experimentally verified.

The purpose of this study is to measure mutual funds' manager performance by attributing it to their abilities to choose better securities (selectivity effect) and to allocate these securities better than their benchmarks (allocation effect). The study enables the authors to examine the relative contributions of the commonly known asset-pricing factors in mutual funds' performance.

To examine managers' ability to steer funds' returns, the authors conduct a two-dimensional holdings-based analysis using factor-specific decomposition of funds' excess returns into their ability to select and allocate securities better than their benchmarks. Subsequently, the authors conduct an analysis of the covariance (ANCOVA) due to these factors in explaining funds' excess returns over time.

While managers' ability to choose better securities than the benchmarks (the selectivity effect) appears modest, some funds (especially the winners) allocate securities in their portfolios better than their benchmarks (the allocation effect) based on their exposures to certain factors (e.g. the momentum factor for the winner funds). However, although funds consistently gain through their ability to predict the size and value factors well, they do not consistently possess the skills to predict the momentum factor.

Although the paper analyzes all the available diversified funds, the sample excludes several other categories, such as thematic and international funds. Further, the analysis is based on equity-oriented Indian funds. Broader studies of changes in factor exposures and the inclusion of more factors apart from those conventionally used may shed more light on the managers' ability to maneuver these factors.

The results show that mutual fund managers lack persistence in their performance, even though some of them could predict specific factors well. Since the activity in active mutual funds could not lead to superior performance over time, investors could be better off by selecting cheaper passive funds for their long-term investments.

The paper presents a novel approach to studying funds' performance by conducting a two-dimensional holdings-based analysis to capture the relative contributions of common asset-pricing factors in the cross-section as well as over time.

The electronics industry will implement lead‐free soldering in the near future. Lead‐free implementation steps are divided into lead‐free process and lead‐free product. The eutectic Sn/Ag/Cu alloy seems to have become the most widely used alloy in the implementation of lead‐free processes. In this study, the requirements for component placement are discussed from the lead‐free process point of view. Experiments concerning the self‐alignment capability and tack strength of both tin‐lead and lead‐free solder pastes are presented. According to the results, a bigger variation in self‐alignment capabilities can be expected when using a lead‐free paste. The paste properties affecting the self‐alignment mechanism and tack strength are also discussed.

This study aims to develop sweet chestnut incorporated corn-based extrudates by the optimization of process conditions.

The independent process variables for extrusion (blend ratio, barrel temperature, screw speed and feed moisture) were investigated to govern their impact on reliant variables, namely, bulk density, specific mechanical energy, water absorption index, water solubility index, color and hardness. Product and system responses were significantly (p < 0.05) affected by the independent variables. Experimental design with quadratic models experienced a high coefficient of determination (R² = 0.99).

Numerical optimization for the development of extrudates resulted in optimum conditions having corn flour: sweet chestnut flour (80:20), barrel temperature (120°C), screw speed (340 rpm) and feed moisture (12%). Fat, moisture and protein contents of the developed extrudates using optimum conditions were significantly (p < 0.05) lower compared to raw materials – corn and sweet chestnut. The packaging of extrudates in aluminum laminates revealed shelf stability of three months at room temperature without deterioration of quality.

Nutritionally rich sweet chestnut extruded products would be an exclusive option to already existing snacks in the market and can facilitate a new sphere in extruded product sector.