Remnant Life Assessment based on the Small Punch Test and the Wilshire Equations
Lead Research Organisation:
Swansea University
Department Name: College of Engineering
Abstract
The Wilshire equations have been widely applied to uniaxial creep test data on a wide range of steel alloys used in power generation and on some Titanium alloys used in aero engines. In all these studies, it has been possible to obtain accurate long-term life predictions from very short-term accelerated uniaxial tests. This suggests that these equations adequately capture the main creep deformation processes.
However, such uniaxial testing cannot be done on components already in use without causing a deterioration in the structural integrity of that part. The small punch test, that uses thin slices of material cut from in use parts, has been put forward as a means of determining remanent life. Numerical models on 1/2Cr1/2Mo1/4V steel have also demonstrated that this test is sensitive to pre-existing damage and so offers the potential to accurately determine this remanent life. Such information is currently invaluable as many power plants within the UK are approaching their original design lives, and the growing potential energy gap within the UK is creating pressure to extend the use of these aging plants.
***** The improved correlation between SP and conventional creep data is ESSENTIAL to underpin data previously generated under numerous Stratigic Partnership Core Research and post graduate projects. *****
However, such uniaxial testing cannot be done on components already in use without causing a deterioration in the structural integrity of that part. The small punch test, that uses thin slices of material cut from in use parts, has been put forward as a means of determining remanent life. Numerical models on 1/2Cr1/2Mo1/4V steel have also demonstrated that this test is sensitive to pre-existing damage and so offers the potential to accurately determine this remanent life. Such information is currently invaluable as many power plants within the UK are approaching their original design lives, and the growing potential energy gap within the UK is creating pressure to extend the use of these aging plants.
***** The improved correlation between SP and conventional creep data is ESSENTIAL to underpin data previously generated under numerous Stratigic Partnership Core Research and post graduate projects. *****
People |
ORCID iD |
| Mark Evans (Primary Supervisor) | |
| Tom Williams (Student) |
Studentship Projects
| Project Reference | Relationship | Related To | Start | End | Student Name |
|---|---|---|---|---|---|
| EP/R512102/1 | 01/10/2017 | 30/09/2022 | |||
| 1939639 | Studentship | EP/R512102/1 | 01/10/2017 | 30/09/2021 | Tom Williams |
| Description | The application of the Wilshire extrapolation technique on a range of Waspaloy and RR1000 time to failure data ranges. This work has been detailed in the form of a journal paper. This paper lays the foundations for the modelling of the Wilshire extrapolation technique. A range of tests have been completed on a series of Waspaloy and RR100 discs at a range of temperatures to produce a suitable range results needed to model the Wilshire technique. |
| Exploitation Route | The outcomes of this project will allow for the quick and accurate production of complete predicted creep curves at any test conditions, including operating conditions, just through the use of accelerated tests data. This work could cut works off the research cycles and allow other engineers so assess the suitablilty of this two alloys in the use of high temperature applications, for example as blade in the HT compressor or large pressure vessels. |
| Sectors | Aerospace, Defence and Marine,Chemicals,Energy |
| URL | https://www.sciencedirect.com/science/article/pii/S0308016118305325 |