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The aim is to focus on the application of X‐rays in the failure analysis of electronic devices and systems, with an emphasis on X‐ray radiography and X‐ray spectroscopy.

The theory behind X‐ray radiography and X‐ray spectroscopy is reviewed, and relevant case studies are used to illustrate the application of these techniques in the failure analysis of electronic devices and systems.

Examples from recent case studies are given.

The paper provides an introduction to X‐ray methods for engineers working on the failure analysis of electronic devices and systems who may be unfamiliar with these techniques.

Organic and immersion metallic coatings are being used as a replacement for the hot air solder level (HASL) process. Use of these coatings provides advantages for both the fabricator and assembler. Advantages to assemblers include flatter pads (0.25‐0.5 micron thickness), no limitations on fine pitch or small hole cleaning, and greater solder joint strength. Advantages to the fabricator include lower operating costs, little or no rejects/rework, reduced safety hazard and a more environmentally friendly process. Current problems associated with the organic and immersion coatings include the inability to assess the solderability of the bare copper or the integrity of the coating (organic). These coatings also present a critical concern due to their reduced shelf life and potential inability to survive mishandling in manufacturing. Real time, non‐destructive methods of rapidly assessing the integrity these coatings are currently not available to the electronics industry. Surface Spectroscopy measurement techniques have the potential to measure the structure and characteristics of the organic and metallic coatings, and surface oxides that develop with time and temperature. The measurement techniques are rapid, non‐contact, and relatively inexpensive to make when compared to existing methods. Surface Spectroscopy can also provide critical surface information that is needed to troubleshoot solderability problems. The American Competitiveness Institute in association with the Navy EMPF program is working with several industry partners to develop a usable surface spectroscopy tool that will assess the quality and integrity of the coatings and correlate that reading with a solderability evaluation.

Residues associated with soldering operations are common throughout the electronics manufacturing industry. Prevention is necessitated by MIL specs which require soldered assemblies to be free of all residues. Because of the large number of variables which contribute to residue formation, residues frequently appear under seemingly constant conditions, and detailed understanding of the materials and processes involved is needed for corrective action implementation. This paper presents the history of an investigation of white residue on solder masked printed wiring assemblies. The residue was determined to be flux related by experimentation and spectroscopic chemical analysis. Process modification testing was performed to evaluate the roles of flux identity, preheater temperatures and several cleaning process variables. Assemblies were subjected to humidity and temperature cycling, including periodic examination and electrical testing. Additionally, information learned during this investigation about a number of residue causes and cures is summarised.

THE CONCLUSIONS of the report ‘Lubrication (Tribology)’—better known as the Jost report— were meant to act as a bucket of cold water to bring industry round to the realisation that it was losing vast amounts of money annually due to various malpractices in the art of lubrication and the resulting consequences. The not inconsiderable financial loss mentioned resulted primarily from three sources; maintenance and replacement costs, losses consequential upon breakdown and increased investment required because of reduced machinery life.

The roles of government and the private sector in the provision of food safety in Russia are explored. The establishment and operation of a private food‐safety company are described and its competitiveness is analysed in the context of the evolving food‐regulatory, policy and economic environments found in a transition economy. Business success is attributed to operational efficiency, customer service and flexible strategic management. Potential threats to sustainability from inadequate regulation are identified. The creation of a viable business is viewed as an exemplar in foreign technical assistance to a country in transition to a market economy.

This paper aims to formulate and prepare a series of alkyd paints with new anticorrosive pigments, eco-friendly to the environment, based on a natural zeolitic rock modified by ion exchange to incorporate passivating cations.

The electrochemical characterization of the painted steel was carried out by conductivity measurements, linear polarization tests, measurements of the corrosion potential and electrochemical noise measurements. Besides, accelerated tests in standard environmental chambers were also carried out.

The results show that clinoptilolite–mordenite-based pigments incorporated in the paint provide acceptable anticorrosive properties, taking into account their low environmental impact and the use of a natural resource of low cost. The inhibitory efficiency of ZLa is higher than 80% and of ZPr is close to 70%. The electrochemical assays of the coated panels with the alkyd paints ZLa and ZPr shows similar behavior.

In this work, good results were obtained with an alkyd resin, but other resins could be tested. Paints could also be formulated with modified zeolites as a complement to others traditional anticorrosive pigments.

These paints could be used for the protection of metal structures in low corrosive environments.

There are not many published works using zeolites as anticorrosive pigments.

A pressure contact connector design was evaluated based on contact load and tested under temperature cycling. The damage induced on gold contact surfaces in a pressure contact connector was examined using visual inspection methods. The connector was subjected to mating and unmating operations, as well as repeated thermal excursions to determine environmental factors which would accelerate damage. Pressure indentations and wear tracks were found on the contact bumps and fingers resulting from the temperature cycling. This wear of the contact finish could make the connector susceptible to corrosion by exposing the base metal after repeated thermal cycling. Wear was assumed to be induced due to insufficient contact pressure between the electrical contacts. An alternative design was examined using finite element analysis which appears to provide a high contact load which should result in a lower contact resistance and less wear.

Different metals have been processed using laser‐based solid freeform fabrication (SFF) processes but very little work has been published on the selective laser melting (SLM) of gold (Au). The purpose of this paper is to check the properties of gold powder and identify suitable processing parameters for SLM of 24 carat gold powder.

A full factorial approach was used to vary the processing parameters and identify suitable processing region for gold powder. The effects of laser processing parameters on the internal porosity of the multi‐layer parts were examined.

The gold powder was found to be cohesive in nature with apparent and tap densities of 9.3 and 10.36 g/cm³, respectively. The reflectance of gold powder was found to be 85 per cent in the infrared range. A very narrow good melting region was identified for gold powder. The balling phenomenon was observed at both low and high scan speeds. The size of droplets in the balling region tended to increase with increasing laser power and decreasing scan speeds. The porosity in gold multi‐layer parts was found to be the minimum for a laser power of 50 W and scan speed of 65 mm/s where most of the porosity was found to be inter‐layer porosity.

This research is the first of its kind directly processing 24 carat gold using SLM, identifying the suitable processing parameters and its effect on the internal porosity and structure of multi‐layer parts.