TY - JOUR
T1 - Failure of AISI 304H stainless steel elbows in a heat exchanger
AU - Bahrami, A.
AU - Mousavi Anijdan, S. H.
AU - Taheri, P.
AU - Yazdan Mehr, M.
PY - 2018
Y1 - 2018
N2 - This work investigates the effects of grain boundary oxidation on the failure of AISI 304H stainless steel elbows in a heat exchanger in a power plant after 8 years of service at 400 °C. Optical and electron microscopes, elemental mapping, electron dispersive spectroscopy (EDS), inductively-coupled plasma atomic energy spectroscopy (ICP-AES) and hardness tester were used to understand the failure mechanism. Elemental mapping of the samples operating for 8 years showed high concentrations of oxygen and carbon at the grain boundaries. Results showed that cracks were propagated along the grain boundaries due to the brittleness of the oxide layer at the boundaries. Results confirmed the intergranular and brittle nature of the fracture. Microhardness profilometry showed that oxidized/carburized grain boundaries are significantly harder than matrix inside grains.
AB - This work investigates the effects of grain boundary oxidation on the failure of AISI 304H stainless steel elbows in a heat exchanger in a power plant after 8 years of service at 400 °C. Optical and electron microscopes, elemental mapping, electron dispersive spectroscopy (EDS), inductively-coupled plasma atomic energy spectroscopy (ICP-AES) and hardness tester were used to understand the failure mechanism. Elemental mapping of the samples operating for 8 years showed high concentrations of oxygen and carbon at the grain boundaries. Results showed that cracks were propagated along the grain boundaries due to the brittleness of the oxide layer at the boundaries. Results confirmed the intergranular and brittle nature of the fracture. Microhardness profilometry showed that oxidized/carburized grain boundaries are significantly harder than matrix inside grains.
KW - 304H stainless steel
KW - Failure
KW - Grain boundary oxidation
KW - Heat exchanger
UR - http://www.scopus.com/inward/record.url?scp=85045654233&partnerID=8YFLogxK
U2 - 10.1016/j.engfailanal.2018.04.006
DO - 10.1016/j.engfailanal.2018.04.006
M3 - Article
AN - SCOPUS:85045654233
SN - 1350-6307
VL - 90
SP - 397
EP - 403
JO - Engineering Failure Analysis
JF - Engineering Failure Analysis
ER -