Scanning Electron Microscope

8 cases · 27 images

Crevice Corrosion in a Subsea System — Aspect Before Analysis

ML00148 / Sep.2018
Brittle Fracture of a 420 SS Barrel Nut
M - Martensitic Stainless SteelP - Barrel NutAp - LiftingCd - Heat Treatment Defect
Cm - Fractography by SEMDf - Brittle Fracture
ML00136 / Jun.2018
Hydrogen Cracks of Subsea Studs
M - Low Alloy Medium Carbon QTP - FastenerAp - SubseaCd - Hydrogen Embrittlement
Cm - Fractography by SEMDf - Brittle Fracture
Fractographic analysis by scanning electron microscopy of the stud fracture surface after opening the cracks.  Brittle intergranular morphology with dimples and quasecleavage micromechanisms indicate that the internal cracks, intergranular, occurred by a hydrogen embrittlement effect during electroplating, and the ductile aspects are probably associated to overloading during torque.
517
ML00127 / May.2018
Hydrogen Cracks of Cadmium Plated Studs
M - Low Alloy Medium Carbon QTP - Allen StudAp - Oil and GasCd - Hydrogen Embrittlement
Cm - Fractography by SEMDf - Fracture
Aspect of the fracture surface of the bolt, after cleaning with a  plastic brush.  Although there is a layer of oxides it is possible to see the intergranular morphology of the fracture, typical of a hydrogen embrittlement mechanism.
1154
ML00126 / Mar.2018
Hydrogen Fracture of Subsea Allen Bolts
M - Low Alloy Medium Carbon QTP - Coated ProductAp - SubseaCd - Hydrogen Embrittlement
Cm - Fractography by SEMDf - Intergranular Fracture
Microscopic image by scanning electron microscope (SEM) of the ring surface that presented pites under fouling deposits.
522
ML00124 / Feb.2018
MIC of a Martensitic Valve Ring
M - Martensitic Stainless SteelP - ForgingAp - EnergyCd - Brittle Behavior
Cm - Surface Aspect by SEMDf - Pitting
ML00079 / Jul.2017
Hydrogen Cracking of a Maritime Chain Link
M - High Strength Low AlloyP - Chain LinkAp - OffshoreCd - Hydrogen Embrittlement
Cm - Micrography by SEMDf - Intergranular Cracking
ML00045 / Aug.2017
Subsea Tubular F6NM Martensitic SS
M - Martensitic Stainless SteelP - Fabrication WeldAp - OffshoreCd - Welding
Cm - Kalling Etched Micrography by SEMDf - Fusion Line
Tempered martensitic microstructure of the knife observed in a transverse section micrography.  There are also secondary carbides (white globules) that increase the material wear resistance.
254
ML00054 / Dec.2018
Cutlery Corrosion
M - Martensitic Stainless SteelP - Foodstuff ArticleAp - KitchenCd - Pitting Corrosion
Cm - Kalling Etched Micrography by SEMDf - Martensite

More from these cases

ML00148 — Brittle Fracture of a 420 SS Barrel NutM - Martensitic Stainless SteelP - Barrel NutAp - LiftingCd - Heat Treatment Defect
ML00148 / Sep.2018
Brittle Fracture of a 420 SS Barrel Nut
M - Martensitic Stainless SteelP - Barrel NutAp - LiftingCd - Heat Treatment Defect
Cm - Fractography by SEMDf - Fracture
ML00148 / Sep.2018
Brittle Fracture of a 420 SS Barrel Nut
M - Martensitic Stainless SteelP - Barrel NutAp - LiftingCd - Heat Treatment Defect
Cm - Fractography by SEMDf - Fracture
ML00148 / Sep.2018
Brittle Fracture of a 420 SS Barrel Nut
M - Martensitic Stainless SteelP - Barrel NutAp - LiftingCd - Heat Treatment Defect
Cm - Fractography by SEMDf - Intergranular Fracture
ML00148 / Sep.2018
Brittle Fracture of a 420 SS Barrel Nut
M - Martensitic Stainless SteelP - Barrel NutAp - LiftingCd - Heat Treatment Defect
Cm - Fractography by SEMDf - Dimples
ML00136 — Hydrogen Cracks of Subsea StudsM - Low Alloy Medium Carbon QTP - FastenerAp - SubseaCd - Hydrogen Embrittlement
ML00136 / Jun.2018
Hydrogen Cracks of Subsea Studs
M - Low Alloy Medium Carbon QTP - FastenerAp - SubseaCd - Hydrogen Embrittlement
Cm - Fractography by SEMDf - Secondary Cracks
ML00136 / Jun.2018
Hydrogen Cracks of Subsea Studs
M - Low Alloy Medium Carbon QTP - FastenerAp - SubseaCd - Hydrogen Embrittlement
Cm - Nital Etched Micrography by SEMDf - Cracks
ML00127 — Hydrogen Cracks of Cadmium Plated StudsM - Low Alloy Medium Carbon QTP - Allen StudAp - Oil and GasCd - Hydrogen Embrittlement
ML00127 / May.2018
Hydrogen Cracks of Cadmium Plated Studs
M - Low Alloy Medium Carbon QTP - Allen StudAp - Oil and GasCd - Hydrogen Embrittlement
Cm - Fractography by SEMDf - Intergranular Cracking
ML00126 — Hydrogen Fracture of Subsea Allen BoltsM - Low Alloy Medium Carbon QTP - Coated ProductAp - SubseaCd - Hydrogen Embrittlement
Detailed aspect of the fracture surface of the bolt, evidencing the intergranular morphology of the fracture (although with an oxide scale), typical of a hydrogen embrittlement mechanism.
114
ML00126 / Mar.2018
Hydrogen Fracture of Subsea Allen Bolts
M - Low Alloy Medium Carbon QTP - Coated ProductAp - SubseaCd - Hydrogen Embrittlement
Cm - Fractography by SEMDf - Intergranular Fracture
ML00124 — MIC of a Martensitic Valve RingM - Martensitic Stainless SteelP - ForgingAp - EnergyCd - Brittle Behavior
ML00124 / Feb.2018
MIC of a Martensitic Valve Ring
M - Martensitic Stainless SteelP - ForgingAp - EnergyCd - Brittle Behavior
Cm - Surface Aspect by SEMDf - Pitting
ML00124 / Feb.2018
MIC of a Martensitic Valve Ring
M - Martensitic Stainless SteelP - ForgingAp - EnergyCd - Brittle Behavior
Cm - Surface Aspect by SEMDf - Pitting
ML00124 / Feb.2018
MIC of a Martensitic Valve Ring
M - Martensitic Stainless SteelP - ForgingAp - EnergyCd - Brittle Behavior
Cm - Surface Aspect by SEMDf - Pitting
ML00124 / Feb.2018
MIC of a Martensitic Valve Ring
M - Martensitic Stainless SteelP - ForgingAp - EnergyCd - Brittle Behavior
Cm - Surface Aspect by SEMDf - Pitting
ML00045 — Subsea Tubular F6NM Martensitic SSM - Martensitic Stainless SteelP - Fabrication WeldAp - OffshoreCd - Welding
ML00045 / Aug.2017
Subsea Tubular F6NM Martensitic SS
M - Martensitic Stainless SteelP - Fabrication WeldAp - OffshoreCd - Welding
Cm - Kalling Etched Micrography by SEMDf - Base Metal
ML00045 / Aug.2017
Subsea Tubular F6NM Martensitic SS
M - Martensitic Stainless SteelP - Fabrication WeldAp - OffshoreCd - Welding
Cm - Kalling Etched Micrography by SEMDf - Weld Metal
ML00054 — Cutlery CorrosionM - Martensitic Stainless SteelP - Foodstuff ArticleAp - KitchenCd - Pitting Corrosion
Detail of the tempered martensitic microstructure with secondary carbides of the knife, observed in a transverse section micrography.
206
ML00054 / Dec.2018
Cutlery Corrosion
M - Martensitic Stainless SteelP - Foodstuff ArticleAp - KitchenCd - Pitting Corrosion
Cm - Kalling Etched Micrography by SEMDf - Martensite
Aspect of the rusted surface after cleaning, showing adhered products at the surface, in regions where the passive layer was destroyed and pitting corrosion occurred.
184
ML00054 / Dec.2018
Cutlery Corrosion
M - Martensitic Stainless SteelP - Foodstuff ArticleAp - KitchenCd - Pitting Corrosion
Cm - Surface Aspect by SEMDf - Corrosion
Detail of the rusted surface. EDS analysis inside the pitting shows a high Cl peak (the bright aspect inside the pitting), indicating that the salt over the surface was responsible for destroying the passive layer and the localized corrosion occurred.
172
ML00054 / Dec.2018
Cutlery Corrosion
M - Martensitic Stainless SteelP - Foodstuff ArticleAp - KitchenCd - Pitting Corrosion
Cm - Surface Aspect by SEMDf - Corrosion
Micrographic aspect of the pitting corrosion at the knife surface.  It is possible to see the typical pitting aspect of a localized corrosion that appears as a small dot at the surface but it is a big crater under the surface.
185
ML00054 / Dec.2018
Cutlery Corrosion
M - Martensitic Stainless SteelP - Foodstuff ArticleAp - KitchenCd - Pitting Corrosion
Cm - Micrography by SEMDf - Pitting
Detail of the micrographic aspect of the pitting corrosion at the knife surface.
168
ML00054 / Dec.2018
Cutlery Corrosion
M - Martensitic Stainless SteelP - Foodstuff ArticleAp - KitchenCd - Pitting Corrosion
Cm - Micrography by SEMDf - Pitting