Ferritic

7 cases · 28 images

Crevice Corrosion in a Subsea System — Aspect Before Analysis

Capture method: Optical Microscope Detail focus: Damage clear all

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Micrography of the longitudinal section from the fork tooth in the scoop. The microstructure is the same as in the scoop close to the handle, ferritic grains equiaxial and uniform, but at the cut surface the structure presents strong plastic deformation generated by a mechanical cutting.
36
VIEW
ML00151 / Dec.2018
Ferritic Stainless Steel of a Flatware Fork
M - Ferritic Stainless SteelP - Foodstuff ArticleAp - KitchenCd - Typical manufacturing
Cm - Micro by OM, HCl + Ethanol + Picric AcidDf - Plastic Deformation
Micrography showing the cracking starting point, in the pipe, exactly at the margin of the weld.
292
VIEW
ML00149 / Dec.2018
Vibration Induced Fatigue in a Gas Piping
M - Low Carbon SteelP - Piping spoolAp - FPSOCd - Vibration Induced Fatigue
Cm - Nital Etched Micrography by OMDf - Margin of the Weld Crack
The longitudinal section of the fitting at the thread shows plastic deformation of the fillets, and a crack at the bottom of the thread.
56
VIEW
ML00103 / Nov.2017
Brittle Fracture of a Free-Cutting Connector
M - Low Carbon SteelP - Machined PartAp - ShipCd - Brittle Fracture
Cm - Nital Etched Micrography by OMDf - Crack
Micrography of the weld metal presenting a martensitic island with microcracks, due to a localized increase in the manganese and silicon content, probably because an active flux was adopted in a condition where a high cleanning action was not required. A high flux-to-wire ratio (>1) could also be an issue.
794
VIEW
ML00067 / May.2017
Cold Cracks in C-Mn SAW Weld Metal
M - CMn SteelP - Fabrication WeldAp - AutomotiveCd - Welding Defect
Cm - Nital Etched Micrography by OMDf - Microcracks
Micrography of the fracture at the superior plate (8 mm thickness). The fracture occurred in the coarse grain heat affected zone.
60
VIEW
ML00069 / May.2017
Liquation Cracks in SAW of Low Carbon Steel
M - Low Carbon SteelP - Fabrication WeldAp - AutomotiveCd - Welding Defect
Cm - Nital Etched Micrography by OMDf - Fracture
The micrography shows the region underbead, of the tube HAZ, responsible for the hydrogen cracking (fracture in the right side of the photo - black). The hardness of the HAZ is about 600 HV.
55
VIEW
ML00052 / Apr.2017
Cold Cracks in API 5CT L80 Tube Welded to a Structural Part
M - Low Alloy SteelP - Seamless tubeAp - OffshoreCd - Welding Defect
Cm - Nital Etched Micrography by OMDf - Cracking
A small sample was removed from the steam drum and the micrography shows that the cracks are intergranular (previous austenite) and located in the weld metal.
285
VIEW
ML00020 / Apr.2017
Intergranular SCC in Boiler Steam Drum Repair
M - Low Carbon SteelP - Repair WeldAp - BoilerCd - Stress Corrosion
Cm - Nital Etched Micrography by OMDf - Corrosion Cracking

More from these cases

ML00151 — Ferritic Stainless Steel of a Flatware ForkM - Ferritic Stainless SteelP - Foodstuff ArticleAp - KitchenCd - Typical manufacturing
Micrographic detail of the strong plastic deformation at the edge of the scoop in the tooth cutting location. The hardness at this region of strong plastc deformation is about 240HV1.
38
VIEW
ML00151 / Dec.2018
Ferritic Stainless Steel of a Flatware Fork
M - Ferritic Stainless SteelP - Foodstuff ArticleAp - KitchenCd - Typical manufacturing
Cm - Micro by OM, HCl + Ethanol + Picric AcidDf - Plastic Deformation
ML00149 — Vibration Induced Fatigue in a Gas PipingM - Low Carbon SteelP - Piping spoolAp - FPSOCd - Vibration Induced Fatigue
Micrographic detail of the cracking starting point, in the pipe, exactly at the margin of the weld.
33
VIEW
ML00149 / Dec.2018
Vibration Induced Fatigue in a Gas Piping
M - Low Carbon SteelP - Piping spoolAp - FPSOCd - Vibration Induced Fatigue
Cm - Nital Etched Micrography by OMDf - Fatigue Crack
Micrography of a section tranverse to the pipe and to the weld between the 8"pipe and the 2" fitting weldolet. The crack starts exactly at the margin of the weld and propagates in the pipe longitudinal direction, in a straight line, not related to any metallurgical aspect.
30
VIEW
ML00149 / Dec.2018
Vibration Induced Fatigue in a Gas Piping
M - Low Carbon SteelP - Piping spoolAp - FPSOCd - Vibration Induced Fatigue
Cm - Micrography by OMDf - Cracking
Micrographic detail of the fatigue crack propagation in the pipe longitudinal direction, in a straight line, not related to any metallurgical aspect.
29
VIEW
ML00149 / Dec.2018
Vibration Induced Fatigue in a Gas Piping
M - Low Carbon SteelP - Piping spoolAp - FPSOCd - Vibration Induced Fatigue
Cm - Micrography by OMDf - Fatigue Crack
Micrography of a section tranverse to the pipe and to the weld between the 8"pipe and the 2" fitting weldolet. The crack starts exactly at the margin of the weld and propagates in the pipe longitudinal direction, in a straight line until it reaches the condition of overloading and through wall final rupture, with strong plastic deformation as can be seen around the crack.
25
VIEW
ML00149 / Dec.2018
Vibration Induced Fatigue in a Gas Piping
M - Low Carbon SteelP - Piping spoolAp - FPSOCd - Vibration Induced Fatigue
Cm - Nital Etched Micrography by OMDf - Plastic Deformation
Micrographic detail of the final fracture by overloading after the fatigue crack propagated almost through the wall thickness. The microstructure presents strong plastic deformation around the crack, in a ferritic pearlitic structure.
29
VIEW
ML00149 / Dec.2018
Vibration Induced Fatigue in a Gas Piping
M - Low Carbon SteelP - Piping spoolAp - FPSOCd - Vibration Induced Fatigue
Cm - Nital Etched Micrography by OMDf - Ductile Fracture
ML00103 — Brittle Fracture of a Free-Cutting ConnectorM - Low Carbon SteelP - Machined PartAp - ShipCd - Brittle Fracture
Micrographic detail of the longitudinal section of the fitting at the thread, showing a crack at the bottom of the thread.
53
VIEW
ML00103 / Nov.2017
Brittle Fracture of a Free-Cutting Connector
M - Low Carbon SteelP - Machined PartAp - ShipCd - Brittle Fracture
Cm - Nital Etched Micrography by OMDf - Crack
Micrographic detail of a cracking with inclusions decohesion at the bottom of the thread.
51
VIEW
ML00103 / Nov.2017
Brittle Fracture of a Free-Cutting Connector
M - Low Carbon SteelP - Machined PartAp - ShipCd - Brittle Fracture
Cm - Nital Etched Micrography by OMDf - Transgranular Cracking
Micrography of a transverse section, perpendicular to the fracture surface, showing lack of plastic deformation during rupture.
50
VIEW
ML00103 / Nov.2017
Brittle Fracture of a Free-Cutting Connector
M - Low Carbon SteelP - Machined PartAp - ShipCd - Brittle Fracture
Cm - Nital Etched Micrography by OMDf - Fracture
Micrography of a transverse section, perpendicular to the fracture surface, showing lack of plastic deformation during rupture.
45
VIEW
ML00103 / Nov.2017
Brittle Fracture of a Free-Cutting Connector
M - Low Carbon SteelP - Machined PartAp - ShipCd - Brittle Fracture
Cm - Nital Etched Micrography by OMDf - Fracture
Micrography of a transverse section, perpendicular to the fracture surface, showing lack of plastic deformation during rupture. Cleavage factes are evident in the ferritic structure close to the fracture surface.
47
VIEW
ML00103 / Nov.2017
Brittle Fracture of a Free-Cutting Connector
M - Low Carbon SteelP - Machined PartAp - ShipCd - Brittle Fracture
Cm - Nital Etched Micrography by OMDf - Fracture
ML00067 — Cold Cracks in C-Mn SAW Weld MetalM - CMn SteelP - Fabrication WeldAp - AutomotiveCd - Welding Defect
Micrography of the fractured region in the center of the fillet weld metal, that is hard due to the increase in the Mn and Si contents.
43
VIEW
ML00067 / May.2017
Cold Cracks in C-Mn SAW Weld Metal
M - CMn SteelP - Fabrication WeldAp - AutomotiveCd - Welding Defect
Cm - Nital Etched Micrography by OMDf - Fracture
Micrography of the weld metal in a cracked region.
41
VIEW
ML00067 / May.2017
Cold Cracks in C-Mn SAW Weld Metal
M - CMn SteelP - Fabrication WeldAp - AutomotiveCd - Welding Defect
Cm - Nital Etched Micrography by OMDf - Cracks
Micrographic detail of the weld metal in a cracked region.
77
VIEW
ML00067 / May.2017
Cold Cracks in C-Mn SAW Weld Metal
M - CMn SteelP - Fabrication WeldAp - AutomotiveCd - Welding Defect
Cm - Nital Etched Micrography by OMDf - Cracks
ML00069 — Liquation Cracks in SAW of Low Carbon SteelM - Low Carbon SteelP - Fabrication WeldAp - AutomotiveCd - Welding Defect
Micrography of the fracture at the fillet weld margin. The fracture occurred in the coarse grain heat affected zone of the superior plate (8 mm thickness).
54
VIEW
ML00069 / May.2017
Liquation Cracks in SAW of Low Carbon Steel
M - Low Carbon SteelP - Fabrication WeldAp - AutomotiveCd - Welding Defect
Cm - Nital Etched Micrography by OMDf - Fracture
Micrography of the fractured region, from the superior plate side, showing that the intergranular cracking occurred at the coarse grain heat affected zone. The structure is bainitic and there are segregated regions in the previous austenite grain boundaries.
50
VIEW
ML00069 / May.2017
Liquation Cracks in SAW of Low Carbon Steel
M - Low Carbon SteelP - Fabrication WeldAp - AutomotiveCd - Welding Defect
Cm - Nital Etched Micrography by OMDf - Intergranular Cracking
Micrography of the fractured region, from the weld metal side, showing that the intergranular cracking occurred at the coarse grain heat affected zone. The structure is bainitic and there are segregated regions in the previous austenite grain boundaries.
127
VIEW
ML00069 / May.2017
Liquation Cracks in SAW of Low Carbon Steel
M - Low Carbon SteelP - Fabrication WeldAp - AutomotiveCd - Welding Defect
Cm - Nital Etched Micrography by OMDf - Intergranular Cracking
ML00020 — Intergranular SCC in Boiler Steam Drum RepairM - Low Carbon SteelP - Repair WeldAp - BoilerCd - Stress Corrosion
The micrography of the small sample removed from the steam drum shows that the cracks are intergranular (previous austenite) and located in the weld metal.
274
VIEW
ML00020 / Apr.2017
Intergranular SCC in Boiler Steam Drum Repair
M - Low Carbon SteelP - Repair WeldAp - BoilerCd - Stress Corrosion
Cm - Nital Etched Micrography by OMDf - Corrosion Cracking
Secondary cracks in the weld metal showing an intergranular morphology. Stress Corrosion Cracking.
249
VIEW
ML00020 / Apr.2017
Intergranular SCC in Boiler Steam Drum Repair
M - Low Carbon SteelP - Repair WeldAp - BoilerCd - Stress Corrosion
Cm - Nital Etched Micrography by OMDf - Corrosion Cracking
Detail of the secondary cracks in the weld metal with intergranular morphology. Stress Corrosion Cracking.
251
VIEW
ML00020 / Apr.2017
Intergranular SCC in Boiler Steam Drum Repair
M - Low Carbon SteelP - Repair WeldAp - BoilerCd - Stress Corrosion
Cm - Nital Etched Micrography by OMDf - Corrosion Cracking
Detail of the intergranular stress corrosion cracking of the drum shell weld repair.
217
VIEW
ML00020 / Apr.2017
Intergranular SCC in Boiler Steam Drum Repair
M - Low Carbon SteelP - Repair WeldAp - BoilerCd - Stress Corrosion
Cm - Nital Etched Micrography by OMDf - Corrosion Cracking