Considerations for the accreditation of small punch creep testing

Abstract

Efforts to extend a pre-existing European Code of Practice (CoP) covering small punch creep and tensile testing into a full International standard procedure are progressing. Swansea Materials Research & Testing Ltd, in collaboration with the academic team based at Swansea University, have been proactive in anticipating some of the key recommendations from the ECISS TC 1010/WG 1 with a view to gaining accreditation for an extensive suite of small punch test equipment. Here, comparisons between the miniaturised form of small punch creep testing will be made to the expectations for calibration and measurement laid down by existing standards for creep testing of conventional scale specimens. In particular, the calibration requirements relating to load, displacement, alignment and temperature measurement will be addressed. With test reproducibility at the forefront of our attention, recent modifications to test rigs to control load application and validation exercises to define small punch temperature distribution will be described. Ultimately, the need to develop an uncertainty budget for small punch creep testing will be highlighted.

Keywords

• accreditation
• small punch creep
• equipment design
• proceduresl