Publication detail

Acoustic Emission Signal Analysis of Steam Piping Materials under Creep Damage Conditions

VLAŠIC, F. MAZAL, P. MAHMOUD, H. SVOBODOVÁ, M.

Original Title

Acoustic Emission Signal Analysis of Steam Piping Materials under Creep Damage Conditions

Type

lecture

Language

English

Original Abstract

The components operating in aggressive environment like corrosive fluids, high temperature and stresses undergo corrosion and corrosion related degradation. One of the significant degradation factors in terms of integrity is erosion-corrosion in piping systems and creep in high pressure pipelines of thermal power plants. Prompt detection and assessment of high-temperature deformation and damage process before failure takes place is most important. Non-destructive testing plays a very important role in providing detection of the early signs of corrosion so that corrective action can be taken before damage becomes severe. This article is focused on analysis of a set of steam piping specimens with different degrees of degradation and dissimilar welded joints coming from creep tests. Material degradation was characterized by acoustic emission (AE) method using their source locations and extracted AE parameters. This method is a widely used non-destructive evaluation technique mainly during periodic testing to insure structural integrity of process plant equipment. It is also very useful in material research. Sources of AE include many different mechanisms of deformation and fracture, in case of creep, such as strain hardening, recovery, precipitation of carbides, cavity formation, etc. In this study, time domain and frequency domain characteristics of AE signals generated by different creep mechanisms are presented. The main task is to find a relationship between crack creation and propagation and AE response. An integral part of this study is also the analysis of noise and other interfering signals coming from outside. Since cracks may grow and propagate very quickly, thus causing sudden failure of the component, it is of paramount importance to be able to detect creep damage in its early stages.

Keywords

creep damage, acoustic emission, crack, high temperature, steam piping

Authors

VLAŠIC, F.; MAZAL, P.; MAHMOUD, H.; SVOBODOVÁ, M.

Released

17. 9. 2019

Publisher

ASNT

Pages from

1

Pages to

11

Pages count

11

URL

https://asnt.org/MajorSiteSections/Events/Upcoming_Events/ISNCM_2019.aspx

BibTex

@misc{BUT158971,
  author="VLAŠIC, F. and MAZAL, P. and MAHMOUD, H. and SVOBODOVÁ, M.",
  title="Acoustic Emission Signal Analysis of Steam Piping Materials under Creep Damage Conditions",
  booktitle="15th International Symposium on Nondestructive Characterization of Materials",
  year="2019",
  pages="1--11",
  publisher="ASNT",
  url="https://asnt.org/MajorSiteSections/Events/Upcoming_Events/ISNCM_2019.aspx",
  note="lecture"
}