Optical Microscope

6 cases · 17 images

Crevice Corrosion in a Subsea System — Aspect Before Analysis

Microstructure: Duplex Ferritic Austenitic Detail focus: Damage clear all

Optical Microscope — sub-branches

As polished micrography 4NaOH Electrolytic Etched Micro 13

Results

SortNewestOldestTitle A-ZTitle Z-A
Large pore in the weld metal, that did not influence in the failure.
59
VIEW
ML00150 / Dec.2018
Vibration Induced Fatigue in a SS Oil Piping
M - Duplex Stainless SteelP - PipingAp - FPSOCd - Vibration Induced Fatigue
Cm - NaOH Electrolytic Etched MicroDf - Pore
Micrography of a longitudinal section of the sleeve, in a region where the surface layer starts detachment. This grey layer is the tugnsten carbide; and the white layer (1000 microns) is a stainless steel. In this case the first TS layer is sound. The substrate is white in the bottom of the figure.
20
VIEW
ML00147 / Aug.2018
WC Layer Detached from a Cast Lean Duplex
M - Lean Duplex Stainless SteelP - Centrifugal CastingAp - ShipCd - Lack of Sealing
Cm - As polished micrographyDf - Layer Detachment
Micrography of a longitudinal section, at the damage surface of the pin, where the thermal spray layer was partially detached and broken. The through layer breaking is ductile, typical of an overloading condition caused by the localized bending of the pin.
109
VIEW
ML00146 / Jul.2018
Plastic Deformation of a SDSS Riser Pin
M - Super Duplex Stainless SteelP - PinAp - O&G Well DrillingCd - Bending
Cm - NaOH Electrolytic Etched MicroDf - Layer Detachment
Low magnification micrographic aspect of the cracking. It is brittle, transgranular and associated to the ferritic/sigma phase interfaces.
54
VIEW
ML00134 / Aug.2020
Brittle Fracture of a Superduplex Valve Body
M - Super Duplex Stainless SteelP - Fabrication WeldAp - SubseaCd - Brittle Fracture
Cm - NaOH Electrolytic Etched MicroDf - Brittle Cracks
Micrographic detail of the region where the cracking was initiated at the internal side of the fitting.
41
VIEW
ML00094 / Sep.2017
MIC of a Subsea Hydraulic Line
M - Super Duplex Stainless SteelP - Fabrication WeldAp - SubseaCd - Brittle Behavior
Cm - NaOH Electrolytic Etched MicroDf - Through Wall Cracking
Macrography transverse to the circunferential weld, longitudinal to the piping, presenting the location, a little far from the welded joint margin, where the through wall cracking is positioned.
160
VIEW
ML00002 / Jan.2018
Preferential Dissolution and Cracks in SDSS
M - Super Duplex Stainless SteelP - Fabrication WeldAp - PipingCd - Preferential Dissolution
Cm - NaOH Electrolytic Etched MicroDf - Through Wall Cracking

More from these cases

ML00150 — Vibration Induced Fatigue in a SS Oil PipingM - Duplex Stainless SteelP - PipingAp - FPSOCd - Vibration Induced Fatigue
Micrography of the fatigue crack propagating in the pipe thickness. Fully flat and not influenced by any microstructure.
52
VIEW
ML00150 / Dec.2018
Vibration Induced Fatigue in a SS Oil Piping
M - Duplex Stainless SteelP - PipingAp - FPSOCd - Vibration Induced Fatigue
Cm - NaOH Electrolytic Etched MicroDf - Fatigue Crack
Micrography of the fatigue crack close to the internal wall, where (only) the final through wall rupture is associated to plastic deformation, as detailed in the next figure.
56
VIEW
ML00150 / Dec.2018
Vibration Induced Fatigue in a SS Oil Piping
M - Duplex Stainless SteelP - PipingAp - FPSOCd - Vibration Induced Fatigue
Cm - NaOH Electrolytic Etched MicroDf - Fatigue Crack
Micrographic detail of the final crack propagation through wall, with plastic deformation.
62
VIEW
ML00150 / Dec.2018
Vibration Induced Fatigue in a SS Oil Piping
M - Duplex Stainless SteelP - PipingAp - FPSOCd - Vibration Induced Fatigue
Cm - NaOH Electrolytic Etched MicroDf - Plastic Deformation
ML00147 — WC Layer Detached from a Cast Lean DuplexM - Lean Duplex Stainless SteelP - Centrifugal CastingAp - ShipCd - Lack of Sealing
Micrography of a longitudinal section of the sleeve, in a region where the surface layer was completely removed. In this position only the stainless steel layer is at the surface. That is why the sealing condition was lost. The substrate is white in the bottom of the figure.
19
VIEW
ML00147 / Aug.2018
WC Layer Detached from a Cast Lean Duplex
M - Lean Duplex Stainless SteelP - Centrifugal CastingAp - ShipCd - Lack of Sealing
Cm - As polished micrographyDf - Layer Detachment
Micrographic detail of a longitudinal section of the sleeve, in a region where the WC (tungsten carbibe) surface layer was degradated and partially removed.
17
VIEW
ML00147 / Aug.2018
WC Layer Detached from a Cast Lean Duplex
M - Lean Duplex Stainless SteelP - Centrifugal CastingAp - ShipCd - Lack of Sealing
Cm - As polished micrographyDf - Layer Detachment
Micrographic detail of the WC (tungsten carbibe) surface layer, degradated and partially removed.
16
VIEW
ML00147 / Aug.2018
WC Layer Detached from a Cast Lean Duplex
M - Lean Duplex Stainless SteelP - Centrifugal CastingAp - ShipCd - Lack of Sealing
Cm - As polished micrographyDf - Layer Detachment
ML00146 — Plastic Deformation of a SDSS Riser PinM - Super Duplex Stainless SteelP - PinAp - O&G Well DrillingCd - Bending
Micrographic detail of the damage surface layer, detached and broken. The substrate is not affected and the rupture of the layer is typically by overloading.
117
VIEW
ML00146 / Jul.2018
Plastic Deformation of a SDSS Riser Pin
M - Super Duplex Stainless SteelP - PinAp - O&G Well DrillingCd - Bending
Cm - NaOH Electrolytic Etched MicroDf - Layer Detachment
ML00134 — Brittle Fracture of a Superduplex Valve BodyM - Super Duplex Stainless SteelP - Fabrication WeldAp - SubseaCd - Brittle Fracture
Micrographic details of the cracking. It is brittle, transgranular and associated to the ferritic/sigma phase interfaces.
50
VIEW
ML00134 / Aug.2020
Brittle Fracture of a Superduplex Valve Body
M - Super Duplex Stainless SteelP - Fabrication WeldAp - SubseaCd - Brittle Fracture
Cm - NaOH Electrolytic Etched MicroDf - Brittle Cracks
Micrographic aspect of the cracking. It is brittle, transgranular and associated to the ferritic/sigma phase interfaces.
49
VIEW
ML00134 / Aug.2020
Brittle Fracture of a Superduplex Valve Body
M - Super Duplex Stainless SteelP - Fabrication WeldAp - SubseaCd - Brittle Fracture
Cm - NaOH Electrolytic Etched MicroDf - Brittle Cracks
ML00002 — Preferential Dissolution and Cracks in SDSSM - Super Duplex Stainless SteelP - Fabrication WeldAp - PipingCd - Preferential Dissolution
Longitudinal section micrography at the cracked position, close to the external surface of the flange, showing cracks transverse to the thickness, associated to the microstructure.
147
VIEW
ML00002 / Jan.2018
Preferential Dissolution and Cracks in SDSS
M - Super Duplex Stainless SteelP - Fabrication WeldAp - PipingCd - Preferential Dissolution
Cm - NaOH Electrolytic Etched MicroDf - Cracks Transverse to the Surface
Longitudinal section micrography at the cracked position, close to the internal surface of the flange (exposed to the corrosive fluid), showing preferential dissolution associated to the microstructure.
133
VIEW
ML00002 / Jan.2018
Preferential Dissolution and Cracks in SDSS
M - Super Duplex Stainless SteelP - Fabrication WeldAp - PipingCd - Preferential Dissolution
Cm - NaOH Electrolytic Etched MicroDf - Preferential Dissolution