Abstract
Data assessments, materials modelling and development as
well as recommendations for model selection have been a
main objective of the ECCC Working Group 1. This paper
describes the latest inter-comparison round robin on
relaxation modelling. Most models found in the public
domain are limited in either strain range or temperature.
Here the bolting steel 1Cr-0.5Mo-0.25V steel tested by
NIMS, Japan is assessed by a number of assessors striving
to define models capable of predicting the relaxation in
the full data range, i.e. in both strain (0.1-0.25% total
strain) and temperature (450-550°C). The assessors use
methods of their own preference giving all model
parameters to enable interpolation/extrapolation and
calculation of prediction errors within the range of
data. The methods include forward creep with different
creep strain models as base, classical relaxation models,
parametric (Time-Temperature-Parameter curve families)
solutions and entirely new modelling approaches. The main
target is the general overall model for prediction of
relaxed stress up to 3 000 h hold time. However, the
model robustness is tested by fitting to a drastically
culled data set consisting of only the short term data
with durations of 0.1 to 10h. The predictive performance
of the models optimised for the short term data are
compared with the long term data as well as the long term
models. Conclusions and recommendations are given on
model interpolation performance, extrapolation ability
and model complexity.
Original language | English |
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Title of host publication | ECCC 2014: Creep & fracture in high temperature components |
Subtitle of host publication | Design & life assessment |
Number of pages | 15 |
ISBN (Electronic) | 978-88-7484-510-1 |
Publication status | Published - 2014 |
MoE publication type | A4 Article in a conference publication |
Event | 3rd International ECCC Conference, ECCC 2014: ECCC 2014 Creep & Fracture in High Temperature Components, Design & Life Assessment - Rome, Italy Duration: 5 May 2014 → 7 May 2014 Conference number: 3 |
Conference
Conference | 3rd International ECCC Conference, ECCC 2014 |
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Abbreviated title | ECCC 2014 |
Country/Territory | Italy |
City | Rome |
Period | 5/05/14 → 7/05/14 |
Keywords
- stress relaxation
- modelling