NPL leads project to investigate solder joint reliability during transition period to lead-free

Citation

(2004), "NPL leads project to investigate solder joint reliability during transition period to lead-free", Soldering & Surface Mount Technology, Vol. 16 No. 2. https://doi.org/10.1108/ssmt.2004.21916bab.011

NPL leads project to investigate solder joint reliability during transition period to lead-free

NPL leads project to investigate solder joint reliability during transition period to lead-free

Keywords: NPL,Lead-free soldering,Reliability

During the run-up to the change over to lead-free (LF) solders by July 2006, a number of end-users have expressed concerns about the reliability of soldered joints formed by mixtures of tin-lead (SnPb) and lead-free materials. These will arise when lead-free components are soldered using SnPb alloys, something already happening in many production lines, and later when SnPb components are soldered with LF alloys. This latter issue may be a significant problem for companies which have had to invest in lifetime purchase of components. Several workers have already published information, which suggests that small levels of Pb contamination in LF joints can significantly reduce joint performance.

Many of those concerned end-users approached NPL to assist with clarification of any reliability issues during the transition period. A consortium of 16 contributing companies was formed (list below) and a work programme agreed. The work will cover the following areas:

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  Reliability assessment of LF joints to SnPb components.

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  Reliability assessment of SnPb joints to LF components.

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  Evaluation of hot-peel strength of Pb- contaminated LF joints.

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  Applicability of Pb indicator kits for paints for recognition of Pb-containing components.

The work, lead by Martin Wickham, is already underway and results are expected in the next 12 months.

Participating partners include:

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  Aeroflex International Ltd,

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  AMS Space UK,

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  BAE SYSTEMS (Operations) Limited,

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  Celestica Ltd,

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  Department of Trade and Industry,

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  Dolby Laboratories, Inc.,

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  Eurotherm Ltd,

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  Goodrich Engine Control Systems,

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  Hansatech Group,

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  National Physical Laboratory,

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  Robert Bosch GmbH,

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  Rolls Royce Naval Marine,

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  TRW Automotive,

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  Thales Missile Electronics Ltd

For more information please contact: Dr Chris Hunt, National Physical Laboratory, Teddington, Middlesex TW11 OLW. Tel: +44(0)20 8943 7027; Fax:+44(0)20 8614 0428; E-mail: chris.hunt@npl.co.uk