Root cause of embrittlement of in-service exposed high pressure steam pipeline

Ohanková, M.; Čmakal, J.; Junek, M.; Kvapilová, Marie; Dvořák, Jiří; Sklenička, Václav

doi:https://dx.doi.org/10.1016/j.prostr.2022.12.275

Number of the records: 1

Root cause of embrittlement of in-service exposed high pressure steam pipeline

1.

SYSNO ASEP	0570444
Document Type	C - Proceedings Paper (int. conf.)
R&D Document Type	Conference Paper
Title	Root cause of embrittlement of in-service exposed high pressure steam pipeline
Author(s)	Ohanková, M. (CZ) Čmakal, J. (CZ) Junek, M. (CZ) Kvapilová, Marie (UFM-A)_{RID, ORCID} Dvořák, Jiří (UFM-A)_{RID, ORCID} Sklenička, Václav (UFM-A)_{RID, ORCID}
Number of authors	6
Source Title	Procedia Structural Integrity, Materials Structure & Micromechanics of Fracture, 43. - Amsterdam : Elsevier B. V., 2023 / Pokluda J. ; Šandera P. - ISSN 2452-3216
Pages	s. 300-305
Number of pages	6 s.
Publication form	Online - E
Action	MSMF10 - International Conference on Materials Structure and Micromechanics of Fracture /10./
Event date	12.09.2022 - 14.09.2022
VEvent location	Brno
Country	CZ - Czech Republic
Event type	WRD
Language	eng - English
Country	NL - Netherlands
Keywords	Steam pipeline ; embrittlement ; microstructure ; mechanical properties ; heat treatment ; low-alloyed steel
Subject RIV	JG - Metallurgy
OECD category	Materials engineering
R&D Projects	TK03020089 GA TA ČR - Technology Agency of the Czech Republic (TA ČR)
Institutional support	UFM-A - RVO:68081723
EID SCOPUS	85159792856
DOI	10.1016/j.prostr.2022.12.275
Annotation	A segment of tube cut off from the high pressure steam pipeline was subjected to routine basic material tests, which resulted in very low impact energy of the pipe material (low-alloyed Cr steel). A part of the segment (and a comparative non-operated sample) was then subjected to detailed mechanical tests (including creep), metallographic investigations and fractographic analyses with an aim to determine a root cause of the embrittlement. The results showed that grain boundaries of exposed steel are covered by particles of primary and secondary cementite. However, a matrix is weakened more, therefore a fracture of creep, tensile and impact specimens is always transgranular and the cleavage facets are limited to grain size, if present. Thus, the cause of embrittlement was determined not by a rapid ageing, but by an unsuitable initial heat treatment of the pipe material.
Workplace	Institute of Physics of Materials
Contact	Yvonna Šrámková, sramkova@ipm.cz, Tel.: 532 290 485
Year of Publishing	2024

Number of the records: 1