Community Research and Development Information Service - CORDIS

Abstract

Plant components operating at elevated temperatures in energy related applications are frequently designed on the known creep data for the construction material. Economic factors favour design for long service lives (> 100,000h) and suitable creep data for such lengths of time are usually unavailable. In order to generate the required data various empirical rules can be implemented based on extrapolation of relatively short term data. Many of these methods rely on a prediction from the steady state (or secondary) creep regime but for many materials this is not satisfactory with regard to either deformation or life time prediction. The austenitic material, Alloy 800 H, extensively used in, or suggested as a candidate material for high temperature plant, is an alloy which would greatly benefit from more accurate creep behaviour prediction methodology in component design. As a contribution towards this goal, creep curves have been obtained for this alloy at temperatures of 800 and 900 degrees C under uniaxial conditions involving both constant load and constant stress. Mathematical functions have been ascribed to these curves following a method similar to that proposed by Evans et al. and the difficulties arising from this approach are emphasized. The constants inherent in the mathematical functions are subsequently analyzed in terms of their interpolation accuracy and extrapolation potential for longer term behaviour, in particular in terms of creep deformation but also lifetime.

Additional information

Authors: TAYLOR N G, JRC PETTEN ESTAB. (THE NETHERLANDS);MCALLISTER A S, JRC PETTEN ESTAB. (THE NETHERLANDS);HURST R C JRC PETTEN ESTAB. (THE NETHERLANDS), JRC PETTEN ESTAB. (THE NETHERLANDS)
Bibliographic Reference: DURABILITY OF ENGINEERING MATERIALS, GALWAY (IRELAND), SEPT. 26-27, 1985 WRITE TO CEC LUXEMBOURG, DG XIII/A2, POB 1907 MENTIONING PAPER E 32357 ORA
Availability: Can be ordered online
Follow us on: RSS Facebook Twitter YouTube Managed by the EU Publications Office Top