Assessment and Quantification of Damage in the Grade 91 Steel PTZ_Final Submitted_.pdf (1.14 MB)
Download fileAssessment and quantification of damage in the grade 91 steel partially transformed zone
conference contribution
posted on 2020-06-08, 14:08 authored by John Siefert, Jonathan Parker, Ryan Maclachlan, xin xie yang, Rachel ThomsonRachel ThomsonDamage in the grade 91 steel partially transformed zone has historically been associated with
many different types of features in the microstructure. Susceptible features responsible for the
nucleation of damage are frequently cited to include particles such as laves phase, coarse M23C6,
inclusions, nitrides, or interactions between creep strong and creep week grains, grain boundaries
and potentially other sources. Few studies have attempted to link these observations on a
statistically relevant basis using 2D or 3D microscopy techniques. In this study, 2D assessment
using scanning electron microscopy (SEM) and quantification techniques such as energy
dispersive x-ray spectroscopy (EDS) and electron backscatter diffraction (EBSD) are utilized in
combination with 3D serial sectioning of large volumes using plasma focused ion beam milling
(P-FIB) and simultaneous EDS to evaluate an interrupted cross-weld creep test. The cross-weld
creep test was performed using a feature-type geometry, in parent material susceptible to the
evolution of creep damage and interrupted at an estimated life fraction of 70%. The findings from
these evaluations provide perspective on the features in the microstructure responsible for the
nucleation and subsequent growth of the observed damage.
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School
- Aeronautical, Automotive, Chemical and Materials Engineering
Department
- Materials