Atlas

3 cases · 19 images

Crevice Corrosion in a Subsea System — Aspect Before Analysis

The fracture surface is flat, shows the graphite nodules and cleavage of the ferritic microstructure, indicating that the material have exceeded the capacity to acomodate the stress.
944
ML00040 / Apr.2017
Brittle Fracture of a Valve Stem
M - Nodular Cast IronP - Valve StemAp - ShipCd - Brittle Fracture
Cm - Fractography by SEMDf - Cleavage Facets
The micrography of a longitudinal section of the pipe, close to the internal surface, shows a general corrosion mechanism (with slow wall thickness loss), although the graphite/matrix interface is corroded preferentially.
569
ML00034 / Apr.2017
45 Years Old Acquaduct Grey Cast Iron
M - Gray Cast ironP - Centrifugally Cast PipeAp - AcquaductCd - General Corrosion
Cm - Nital Etched Micrography by OMDf - Corrosion
The intake valve seat cylinder, manufactured in a high alloy white cast iron, presents a network of primary carbides, not degradated even after high temperature exposition during all lifetime.
632
ML00003 / Apr.2017
Cast iron Engine Valve Seats
M - White Cast IronP - Valve SeatAp - MaritimeCd - Microstructural Evolution
Cm - Micrography by OMDf - Network of Primary Carbides

More from these cases

ML00040 — Brittle Fracture of a Valve StemM - Nodular Cast IronP - Valve StemAp - ShipCd - Brittle Fracture
Detail of the cleavage micromechanism.
195
ML00040 / Apr.2017
Brittle Fracture of a Valve Stem
M - Nodular Cast IronP - Valve StemAp - ShipCd - Brittle Fracture
Cm - Fractography by SEMDf - Cleavage Facets
The cast iron microstructure is predominatly ferritic with graphite nodules.
169
ML00040 / Apr.2017
Brittle Fracture of a Valve Stem
M - Nodular Cast IronP - Valve StemAp - ShipCd - Brittle Fracture
Cm - Nital Etched Micrography by OMDf - Graphite in Nodules
The micrography of the stem at the fracture region shows a flat fracture with transgranular clevage at the ferritic structure.
137
ML00040 / Apr.2017
Brittle Fracture of a Valve Stem
M - Nodular Cast IronP - Valve StemAp - ShipCd - Brittle Fracture
Cm - Nital Etched Micrography by OMDf - Fracture
Micrography presenting a detail of the fracture surface opening to the graphite nodules.
139
ML00040 / Apr.2017
Brittle Fracture of a Valve Stem
M - Nodular Cast IronP - Valve StemAp - ShipCd - Brittle Fracture
Cm - Nital Etched Micrography by OMDf - Fracture
ML00034 — 45 Years Old Acquaduct Grey Cast IronM - Gray Cast ironP - Centrifugally Cast PipeAp - AcquaductCd - General Corrosion
Micrographic detail of the graphite/matrix interface corrosion, leading to a general corrosion loss.
189
ML00034 / Apr.2017
45 Years Old Acquaduct Grey Cast Iron
M - Gray Cast ironP - Centrifugally Cast PipeAp - AcquaductCd - General Corrosion
Cm - Nital Etched Micrography by OMDf - Graphite in Flakes
Micrography of the longitudinal section of the pipe, close to the internal surface, showing graphite in flakes and ferritic matrix with small regions of perlite.
231
ML00034 / Apr.2017
45 Years Old Acquaduct Grey Cast Iron
M - Gray Cast ironP - Centrifugally Cast PipeAp - AcquaductCd - General Corrosion
Cm - Nital Etched Micrography by OMDf - Predominantly Ferritic Matrix
Micrography of the longitudinal section of the pipe, close to the internal surface, showing graphite in flakes and ferritic matrix with small regions of perlite and eutetic in the middle of the perlite colonies.
192
ML00034 / Apr.2017
45 Years Old Acquaduct Grey Cast Iron
M - Gray Cast ironP - Centrifugally Cast PipeAp - AcquaductCd - General Corrosion
Cm - Nital Etched Micrography by OMDf - Predominantly Ferritic Matrix
Micrography of the longitudinal section of the pipe, in the center of the thickness. Graphite in flakes and ferritic matrix with small regions of perlite.
179
ML00034 / Apr.2017
45 Years Old Acquaduct Grey Cast Iron
M - Gray Cast ironP - Centrifugally Cast PipeAp - AcquaductCd - General Corrosion
Cm - Nital Etched Micrography by OMDf - Predominantly Ferritic Matrix
Micrography of the longitudinal section of the pipe, in the center of the thickness. Graphite in flakes and ferritic matrix with small regions of perlite.
162
ML00034 / Apr.2017
45 Years Old Acquaduct Grey Cast Iron
M - Gray Cast ironP - Centrifugally Cast PipeAp - AcquaductCd - General Corrosion
Cm - Nital Etched Micrography by OMDf - Ferrite and Pearlite

+4 more from this case →

ML00003 — Cast iron Engine Valve SeatsM - White Cast IronP - Valve SeatAp - MaritimeCd - Microstructural Evolution
The intake valve seat cylinder, manufactured in a high alloy white cast iron, presents a network of primary carbides, not degradated even after high temperature exposition during all lifetime.
206
ML00003 / Apr.2017
Cast iron Engine Valve Seats
M - White Cast IronP - Valve SeatAp - MaritimeCd - Microstructural Evolution
Cm - Micrography by OMDf - Network of Primary Carbides
The exhaust valve seat cylinder, manufactured in a high alloy white cast iron, presents a coalesced structure, degradated by high temperature exposition during the lifetime.
182
ML00003 / Apr.2017
Cast iron Engine Valve Seats
M - White Cast IronP - Valve SeatAp - MaritimeCd - Microstructural Evolution
Cm - Micrography by OMDf - Coalesced structure
The exhaust valve seat cylinder, manufactured in a high alloy white cast iron, presents a coalesced structure, degradated by high temperature exposition during the lifetime.
137
ML00003 / Apr.2017
Cast iron Engine Valve Seats
M - White Cast IronP - Valve SeatAp - MaritimeCd - Microstructural Evolution
Cm - Micrography by OMDf - Coalesced structure