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To demonstrate a method of selecting base materials for lead‐free processing based on the kinetics of decomposition.

The paper describes the calculation of Arrhenius kinetic parameters from common “time to delamination” data (T₂₆₀). Delamination is correlated to a certain conversion into the decomposition reaction. With both of these parameters, various soldering scenarios are analysed.

The findings highlight the fact that conventional FR‐4 materials are only good for a few reflow cycles. A higher number of reflow cycles can only be fulfilled with RoHS compliant base materials. However, rework and repair may even shift those more thermally resiliant materials over the limit. The peak temperatures are over proportionally responsible for delamination failures and need to be controlled carefully.

The value of the paper lies in its ability to provide guidance on the selection of base materials to comply with various soldering processes. A model has been developed that is able to predict failure limit for a given base material and a given process.

This paper reflects the ideas on the subject of the Internet presented by four German experts at the German Language Session which took place during the 19th International Information Online Meeting in London, 5‐7 December 1995. The German Language Session was chaired again by Kristina Voigt of the GSF‐Research Centre for Environment and Health in Neuherberg, near Munich, Germany. As both the panel members and the Chairperson felt that the ideas given in their short presentations should be made available to a wider audience, they all agreed to give extended abstracts of their contributions for publication in this international journal. This procedure should give not only the German‐speaking community, but also other international interested parties the oppor‐tunity to be informed on the topics discussed.

ARNOLD BENNETT was a man of two worlds. In the terms of Max Beerbohm's cartoon “Old Self” was plump, wealthy, self‐assured, a landmark of the London scene, a familiar of press magnates, the owner of a yacht; “Young Self” was thin, ambitious, far‐sighted, industrious, secretly terribly anxious to justify himself to himself and decidedly provincial.