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Competitive and Sustainable Growth (Growth) Programme NPL Report DEM-ES 001 COMPETITIVE AND SUSTAINABLE GROWTH (GROWTH) PROGRAMME Final report (open version) on activities within the RTD Project G6RD-CT-2000-00210 “Techniques and materials for the measurement of DC and AC conductivity of non-ferrous metals and alloys” “Conductivity” May 2004 NPL Report DEM-ES 001 G6RD-CT-2000-00210 “Conductivity” page 1 of 149 May 2004 COMPETITIVE AND SUSTAINABLE GROWTH (GROWTH) PROGRAMME Final report (open version) on activities within the RTD Project G6RD-CT-2000-00210 “Techniques and materials for the measurement of DC and AC conductivity of non-ferrous metals and alloys” “Conductivity” Project duration 01.10.2000 to 31.07.2003 Project Co-ordinator: NPL Management Ltd UK Contractors: Physikalisch-Technische Bundesanstalt DE Nederlands Meetinstituut BV NL EADS Space Transportation (formerly EADS Launch Vehicles) F Hocking NDT Limited UK Institut Dr Friedrich Foerster, Prufgeratebau GmbH & Co KG DE Report authors: NPLML: LCA Henderson, MJ Hall, SAC Harmon, G Ashcroft PTB: P Warnecke, B Schumacher NMi: G Rietveld EADS: G Brigodiot Hocking: C Hocking, A White IFR: R Bodenberger NPL Report DEM-ES 001 G6RD-CT-2000-00210 “Conductivity” page 2 of 149 May 2004 ISSN number 1744-0475 Crown Copyright 2004 Reproduced by permission of the Controller of HMSO National Physical Laboratory Teddington, Middlesex, UK, TW11 0LW This document has been produced for the European Commission within the Competitive and Sustainable Growth (Growth) Programme of Framework Programme V under contract number G6RD-CT-2000-00210. Extracts from this report may be reproduced provided the aforementioned contract is acknowledged and the extract is not taken out of context. It describes work undertaken by a consortium of 6 partners. We also acknowledge the financial support of the UK Department of Trade and Industry (National Measurement System Policy Unit). Approved on behalf of Managing Director, NPL, by Dr Stuart Pollitt, Director, Division of Enabling Metrology NPL Report DEM-ES 001 G6RD-CT-2000-00210 “Conductivity” page 3 of 149 May 2004 Contents Contents .....................................................................................................................................3 Project Summary........................................................................................................................5 Summary of Workpackages.......................................................................................................7 Deliverables ...........................................................................................................................7 Milestones..............................................................................................................................7 Workpackage 0 ......................................................................................................................7 Workpackage 1 Management report......................................................................................8 Workpackage 2 ......................................................................................................................9 Task 2.1 Report from NPLML...........................................................................................9 Task 2.2 Report from PTB...............................................................................................10 Task 2.3 Report from IFR................................................................................................15 Task 2.3 Report from NPLML.........................................................................................15 Task 2.4 Report from NPLML.........................................................................................18 Workpackage 3 ....................................................................................................................19 Task 3.1 Report from NMi...............................................................................................19 Task 3.1 Report from PTB...............................................................................................31 Task 3.2 Report from PTB...............................................................................................38 Task 3.3 Report from NPLML.........................................................................................43 Workpackage 4 ....................................................................................................................60 Workpackage 5 ....................................................................................................................61 Task 5.1 Analysis of the results of the standards laboratory results................................61 Task 5.2 Analysis of the results of the industrial user results..........................................67 Deliverable D4 Report on user results.............................................................................67 Comparison of the measurement protocols......................................................................67 Analysis of the results......................................................................................................67 Differences between the Industrial Users Results ...........................................................72 Uncertainty Evaluations...................................................................................................73 General Conclusions ........................................................................................................75 Annex 5.2A : Measurement Protocol - IFR.....................................................................76 Annex 5.2B : Measurement Protocol - HOCKING.........................................................78 Annex 5.2C : Measurement Protocol EADS ...................................................................80 Annex 5.2D : Differences between the Industrial Users Results.....................................81 Task 5.3 Overview of results of project...........................................................................82 Technological Implementation Plan and Forward Look .........................................................87 References................................................................................................................................87 Annex A Notes from the Conductivity workshop...............................................................89 Key points from discussions ............................................................................................90 Presentations ....................................................................................................................90 Detailed questions and discussion ...................................................................................91 Attendance list .................................................................................................................93 Annex B-1 First Contract between PTB and Stahlzentrum Freiberg .................................94 Annex B-2 First Report from Stahlzentrum Freiberg.........................................................96 Annex C-1 Second Contract between PTB and Stahlzentrum Freiberg...........................109 Annex C-2 Second Report from Stahlzentrum Freiberg ..................................................111 Annex D PTB Measurement Report..................................................................................126 Physikalisch-Technische Bundesanstalt ................................................................................127 NPL Report DEM-ES 001 G6RD-CT-2000-00210 “Conductivity” page 4 of 149 May 2004 Annex E Measurement Report from NMi.........................................................................136 Annex F EUROMET project 427 Protocol.......................................................................141 Annex G People involved in the project............................................................................147 Annex H Resource Summary ............................................................................................149 NPL Report DEM-ES 001 G6RD-CT-2000-00210 “Conductivity” page 5 of 149 May 2004 Project Summary Eddy current conductivity measurements are used as a routine inspection method for vast quantities of aluminium alloys used in aircraft manufacture. The relationship between the mechanical hardness and the electrical conductivity of individual alloys has been well established. Thus for the aerospace industry, conductivity measurements form a very important quality assurance which is directly reflected in the safety of an aircraft. Conductivity is also increasingly used in the specification of coins and in the detection of coins in sorting, handling and vending processes. Thus for these industries it forms part of the tools for combating fraud. The majority of conductivity reference standards produced by manufacturers of eddy current conductivity meters are traceable through conductivity standards measured using a direct current method. This would be a satisfactory situation if the materials had uniform properties throughout their thickness. Most of the reference standards produced in this way for the aerospace industry are special alloys of aluminium which undergo grain stretching and precipitate hardening processes. The coin industry has its main interest in conductivities in the range 4 – 18 %IACS. In many cases the finished material has different conductivity values in the surface layers to that of the bulk of the
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