Mechanical testing labs (tensile, impact, toughness, fatigue, crack growth ...) are increasingly required to include in their test reports the uncertainties affecting the data they have measured. However, the possibility to indicate the uncertainties for the measured parameters is often made difficult by a number of aspects which are peculiar to the mechanical tests:
- the sample may be destroyed as a consequence of the measurement, so that exact test repetition is impossible,
- several comparison tests have to be performed to get appropriate statistical amount of data (in order to deal with material homogeneity aspects and inherent test measure scatter),
- reference data (from Certified Reference Materials, CRM) rarely exist.
Detailed procedures for the determination of uncertainties in all measured test parameters on metallic materials do not exist.
The aim of UNCERT project is to formulate the procedures for uncertainty evaluation in mechanical tests on metals (code of practice). The procedures will be defined as the best (in terms of cost/benefit criterion) among several existing options, namely theoretical combinations of uncertainties in directly measured quantities derived from instrumentation tolerances, direct comparisons with CRM's, and possible use of statistical methods (e.g. advanced methods based on fuzzy analysis, pattern recognitions ..).
Funding SchemeCSC - Cost-sharing contracts
ST17 4LN Stafford
20009 San Sebastián
PA4 8DJ Renfrew
TW11 0LW Teddington
7300 AM Apeldoorn
461 81 Trollhättan