Abstract

The testing details and results of a series of service-cycle thermomechanical fatigue (TMF) tests on two heats of a 1CrMoV steam turbine rotor steel are described. Two unexpected features of the tests were the development of testpiece necking and, in one heat of the steel, noninteracting creep and fatigue damage. The paper provides a detailed consideration of these aspects.

Both features are attributed to the magnitude of the temperature gradient along the testpiece gage length at peak temperature during TMF cycling. The temperature gradient was acceptable according to the current draft ISO Standard for TMF testing. In the light of the experience described, it is recommended that this existing guidance be reviewed.

Issue Section:
Research Papers
Keywords:
thermomechanical fatigue, creep-fatigue damage, 1CrMoV steel

References

1.
Timo
,
D. P.
, “
Designing Turbine Components for Low-Cycle Fatigue
,”
Proceedings, International Conference on Thermal Stresses and Fatigue
,
Berkeley
,
1969
, p. 453.
2.
Mayer
,
K-H.
 and
Tremmel
,
D.
, “
The Thermal Fatigue of Components in Steam Power Plant
,”
Proceedings, International DVM Symposium on Low Cycle Fatigue Strength and Elasto-Plastic Behaviour of Materials
,
Stuttgart
, October 8/9, 1979.
3.
Harkegard
,
G.
, “
Designing Steam Turbines for Transient Thermal Loading
,”
Proceedings, International Conference on High Temperature Structural Design, ESIS 12
,
Mechancial Engineering Publications
,
London
,
1984
, p. 21.
4.
Dawson
,
R. A. T.
, “
Monitoring and Control of Thermal Stress and Component Life Expenditure in Steam Turbines
,”
Proceedings, International Conference on Modern Power Stations
,
AIM
,
Liege
,
09
1989
.
5.
Bhongbhibhat
,
S.
, “
Untersuchungen uber das Werkstoffverhalten in Gebiet der Zeitfestigkeit zur Erstellung von Berechnungsunterlagen fur Uberwiegend Thermisch Beanspruchte Bauteille
,”
Techn.-wiss. Ber.
,
MPA Stuttgart
,
Heft
1979
, pp.
79
–
02
.
6.
Thomas
,
G.
 and
Dawson
,
R. A. T.
, “
The Effect of Dwell Period and Cycle Type on High Strain Fatigue Properties of 1CrMoV Rotor Forgings at 500–550°C
,”
Proceedings, International Mechanical Engineering Conference on Engineering Aspects of Creep
,
Sheffield
,
1980
, Paper C335/80.
7.
Miller
,
D. A.
,
Priest
,
R. H.
, and
Ellison
,
E. G.
, “
A Review of Material Response and Life Prediction Techniques under Fatigue-Creep Loading Conditions
,”
High Temperature Materials and Processes
 1093-3611, Vol.
6
, Nos.
3
,
4
,
1984
, pp.
155
–
194
.
8.
Bicego
,
V.
,
Fossati
,
C.
, and
Ragazzoni
,
S.
, “
Low Cycle Fatigue Characterisation of a HP-IP Steam Turbine Rotor
,”
Low Cycle Fatigue, ASTM STP 942
,
ASTM International
,
West Conshohocken, PA
,
1988
, pp.
1237
–
1260
.
9.
Kuwabara
,
K.
 and
Nitta
,
A.
,
Isothermal and Thermal Fatigue Strength of CrMoV Steel for Turbine Rotors
, CRIEPI Report E277005,
1977
.
10.
Westwood
,
H. J.
 and
Lee
,
W. K.
, “
Creep-Fatigue Crack Initiation in 1/2CrMoV Steel
,”
Proceedings, International Conference on Creep and Fracture of Engineering Materials and Structures
,
Swansea
,
Pineridge Press
,
1981
, pp.
517
–
30
.
11.
Colombo
,
F.
,
Masserey
,
B.
,
Mazza
,
E.
, and
Holdsworth
,
S. R.
, “
Simple Modelling of the Constitutive Behaviour of a 1%CrMoV Rotor Steel in Service-Like Thermo-Mechanical Fatigue Tests
,”
Materials at High Temperature
 0960-3409, Vol.
19
, No.
4
,
2002
, pp.
225
–
233
.
Google Scholar
Crossref
Search ADS
 
12.
Masserey
,
B.
,
Colombo
,
F.
,
Mazza
,
E.
, and
Holdsworth
,
S. R.
, “
Factors Influencing the Service-Like Thermo-Mechanical Fatigue Test Cycle Endurance of 1%CrMoV Rotor Steel
,”
Fatigue & Fracture of Engineering Materials & Structures
 8756-758X, Vol.
26
,
2003
, pp.
1041
–
1052
.
Google Scholar
Crossref
Search ADS
 
13.
ISO/TC164/SC5/WG9,
Thermo-Mechanical Fatigue Testing Method
, Working Document,
2002
.
14.
PrEN3988,
Test Methods for Metallic Materials-Constant Amplitude Strain-Controlled Low Cycle Fatigue Testing
,
1995
.
This content is only available via PDF.
All rights reserved. This material may not be reproduced or copied, in whole or in part, in any printed, mechanical, electronic, film, or other distribution and storage media, without the written consent of ASTM International.
You do not currently have access to this content.