Optical Microscope

183 cases · 1637 images

Crevice Corrosion in a Subsea System — Aspect Before Analysis

Micrography as polished of the longitudinal section of the bolt at the fracture position.  The fracture (top of the figure) is rough, characteristic of a ductile fracture.
196
ML00120 / Jun.2018
Ductile Rupture of a Carbon Steel Eye Bolt
M - Low Carbon SteelP - FastenerAp - AutomotiveCd - Overload
Cm - As polished micrographyDf - Fracture
Micrography of the plate in a longitudinal section, presenting a typical ferritic pearlitic structure, banded.  The plate is 22 mm thick.
182
ML00119 / Feb.2018
Thermal Fatigue of a Marine Boiler
M - Low Carbon SteelP - Fabrication WeldAp - ShipCd - Thermal Fatigue
Cm - Nital Etched Micrography by OMDf - Banded Structure
Micrography of the welded joint, at the root, presenting hot cracks.  The imposed high energy in the root due to the ceramic backing support created a condition for cracking.
1100
ML00118 / Jan.2018
Non qualified GMAW of Aluminum Plates
M - Aluminum Magnesium ManganeseP - Welded Testpiece for QualificationAp - ShipCd - Non qualified
Cm - Keller Etched Micrography by OMDf - Hot cracking
Micrography of a longitudinal section of the core wire, 2.0 mm diameter, in the center of the thickness, showing a strain hardened structure, aligned.
113
ML00117 / Jan.2018
High Carbon Steel Wire Rope
M - High Carbon SteelP - Wire RopeAp - Oil and GasCd - Typical manufacturing
Cm - Nital Etched Micrography by OMDf - In the Center of the Thickness
ML00110 / Jan.2018
Non Conformance in Spray and Fuse Pin
M - Low Alloy Medium Carbon QTP - Tubular ForgingAp - O&G Well DrillingCd - Heat Treatment Defect
Cm - As polished micrographyDf - Transverse Section
Micrographic detail of a transverse section of the tubing, in the center of the thickness. Ferritic-pearlitic structure. Pearlite colonies in bands.
401
ML00116 / Jan.2018
CMn Steel Structural Tubing 6 mm thick
M - CMn SteelP - Seamless Round ShapeAp - StructureCd - Removed From Service
Cm - Nital Etched Micrography by OMDf - Ferrite and Pearlite
Micrographic detail of a transverse section of the 5 mm thick tubing, in the center of the thickness. Ferritic-pearlitic structure, with the pearlite presenting a coalesced aspect.  The tubing was in service at ambient temperature, painted, and the coalesced aspect was generated before service, perhaps during the tubing manufacturing.
393
ML00115 / Jan.2018
CMn Steel Structural Tubing 5 mm thick
M - CMn SteelP - Seamless Round ShapeAp - StructureCd - Removed From Service
Cm - Nital Etched Micrography by OMDf - Ferrite and Pearlite
Micrographic detail of a transverse section of the tubing, in the center of the thickness.  
Ferritic-pearlitic structure. 
Pearlite colonies in bands.
346
ML00114 / Jan.2018
CMn Steel Structural Tubing 8 mm thick
M - CMn SteelP - Seamless Round ShapeAp - StructureCd - Removed From Service
Cm - Nital Etched Micrography by OMDf - Ferrite and Pearlite

More from these cases

ML00120 — Ductile Rupture of a Carbon Steel Eye BoltM - Low Carbon SteelP - FastenerAp - AutomotiveCd - Overload
Micrography of a longitudinal section of the bolt in the center of the thickness, presenting a ferritic pearlitic structure with elongated grains due to the forming process, without later heat treatment.
173
ML00120 / Jun.2018
Ductile Rupture of a Carbon Steel Eye Bolt
M - Low Carbon SteelP - FastenerAp - AutomotiveCd - Overload
Cm - Nital Etched Micrography by OMDf - Ferrite and Pearlite
Micrographic detail of the ferritic pearlitic structure, with grains sligthly elongated.
157
ML00120 / Jun.2018
Ductile Rupture of a Carbon Steel Eye Bolt
M - Low Carbon SteelP - FastenerAp - AutomotiveCd - Overload
Cm - Nital Etched Micrography by OMDf - Ferrite and Pearlite
Micrography of a longitudinal section of the bolt at the bottom of the thread fillet, presenting a plastically deformed ferritic pearlitic structure in a very small extension from the surface (about 0.1mm). This analysis was conducted in a position far from the failure and the structure was created by the cold forming process to manufacture the thread.
151
ML00120 / Jun.2018
Ductile Rupture of a Carbon Steel Eye Bolt
M - Low Carbon SteelP - FastenerAp - AutomotiveCd - Overload
Cm - Nital Etched Micrography by OMDf - Rolled Thread
Micrographic detail of a longitudinal section of the bolt at the bottom of the thread fillet, presenting a plastically deformed ferritic pearlitic structure.  This analysis was conducted far from the failure and the structure was created by the cold forming process to manufacture the thread.
147
ML00120 / Jun.2018
Ductile Rupture of a Carbon Steel Eye Bolt
M - Low Carbon SteelP - FastenerAp - AutomotiveCd - Overload
Cm - Nital Etched Micrography by OMDf - Strain Hardened
Micrography of a longitudinal section of the bolt at the thread fillet adjacent to the fracture, presenting a ductile cracking from the bottom of the fillet, propagating with a strong plastic deformation. 
The deformation lines of the cold formed process (thread cold rolling) are also deformed by the cracking propagation.
141
ML00120 / Jun.2018
Ductile Rupture of a Carbon Steel Eye Bolt
M - Low Carbon SteelP - FastenerAp - AutomotiveCd - Overload
Cm - Nital Etched Micrography by OMDf - Ductile Crack

+1 more from this case →

ML00119 — Thermal Fatigue of a Marine BoilerM - Low Carbon SteelP - Fabrication WeldAp - ShipCd - Thermal Fatigue
Micrography of the plate in a longitudinal section, presenting a typical ferritic pearlitic structure, banded.
165
ML00119 / Feb.2018
Thermal Fatigue of a Marine Boiler
M - Low Carbon SteelP - Fabrication WeldAp - ShipCd - Thermal Fatigue
Cm - Nital Etched Micrography by OMDf - Ferrite and Pearlite
Micrographic detail of the ferritic pearlitic structure of the plate in the longitudinal section.
147
ML00119 / Feb.2018
Thermal Fatigue of a Marine Boiler
M - Low Carbon SteelP - Fabrication WeldAp - ShipCd - Thermal Fatigue
Cm - Nital Etched Micrography by OMDf - Ferrite and Pearlite
Micrography of the weld metal in the center os the weld. Columnar grains (of the previous austenite) with primary ferrite in the grain boundaries; ferrite with aligned second phases and acicular ferrite, intragranular.
137
ML00119 / Feb.2018
Thermal Fatigue of a Marine Boiler
M - Low Carbon SteelP - Fabrication WeldAp - ShipCd - Thermal Fatigue
Cm - Nital Etched Micrography by OMDf - Weld Metal
Micrography of the weld metal in the center os the weld. Columnar grains (of the previous austenite) with primary ferrite in the grain boundaries and acicular ferrite intragranular.
125
ML00119 / Feb.2018
Thermal Fatigue of a Marine Boiler
M - Low Carbon SteelP - Fabrication WeldAp - ShipCd - Thermal Fatigue
Cm - Nital Etched Micrography by OMDf - Ferritic Weld Metal
Micrographic detail of the weld metal in the center os the weld. Columnar grains (of the previous austenite) with primary ferrite in the grain boundaries; and details of the ferrite with aligned second phases and acicular ferrite, intragranular.
112
ML00119 / Feb.2018
Thermal Fatigue of a Marine Boiler
M - Low Carbon SteelP - Fabrication WeldAp - ShipCd - Thermal Fatigue
Cm - Nital Etched Micrography by OMDf - Ferritic Weld Metal

+12 more from this case →

ML00118 — Non qualified GMAW of Aluminum PlatesM - Aluminum Magnesium ManganeseP - Welded Testpiece for QualificationAp - ShipCd - Non qualified
Micrography of the welded joint, at the root, showing hot cracks with intergranular morphology.
146
ML00118 / Jan.2018
Non qualified GMAW of Aluminum Plates
M - Aluminum Magnesium ManganeseP - Welded Testpiece for QualificationAp - ShipCd - Non qualified
Cm - Keller Etched Micrography by OMDf - Hot cracking
Micrographic detail of the welded joint, at the root, presenting hot cracks.  The presence of these defects were responsible for reducing the material strenght (rupturing in lower strenght than the requirements) and ductility (cracking in bending tests).
116
ML00118 / Jan.2018
Non qualified GMAW of Aluminum Plates
M - Aluminum Magnesium ManganeseP - Welded Testpiece for QualificationAp - ShipCd - Non qualified
Cm - Keller Etched Micrography by OMDf - Hot cracking
ML00118 / Jan.2018
Non qualified GMAW of Aluminum Plates
M - Aluminum Magnesium ManganeseP - Welded Testpiece for QualificationAp - ShipCd - Non qualified
Cm - Keller Etched Micrography by OMDf - Base Metal
ML00118 / Jan.2018
Non qualified GMAW of Aluminum Plates
M - Aluminum Magnesium ManganeseP - Welded Testpiece for QualificationAp - ShipCd - Non qualified
Cm - Keller Etched Micrography by OMDf - Base Metal
ML00118 / Jan.2018
Non qualified GMAW of Aluminum Plates
M - Aluminum Magnesium ManganeseP - Welded Testpiece for QualificationAp - ShipCd - Non qualified
Cm - Keller Etched Micrography by OMDf - Base Metal

+6 more from this case →

ML00117 — High Carbon Steel Wire RopeM - High Carbon SteelP - Wire RopeAp - Oil and GasCd - Typical manufacturing
ML00117 / Jan.2018
High Carbon Steel Wire Rope
M - High Carbon SteelP - Wire RopeAp - Oil and GasCd - Typical manufacturing
Cm - Nital Etched Micrography by OMDf - Longitudinal Section
ML00117 / Jan.2018
High Carbon Steel Wire Rope
M - High Carbon SteelP - Wire RopeAp - Oil and GasCd - Typical manufacturing
Cm - Nital Etched Micrography by OMDf - Strain hardened pearlite
ML00117 / Jan.2018
High Carbon Steel Wire Rope
M - High Carbon SteelP - Wire RopeAp - Oil and GasCd - Typical manufacturing
Cm - Nital Etched Micrography by OMDf - At the Surface
ML00117 / Jan.2018
High Carbon Steel Wire Rope
M - High Carbon SteelP - Wire RopeAp - Oil and GasCd - Typical manufacturing
Cm - Nital Etched Micrography by OMDf - Longitudinal Section
ML00117 / Jan.2018
High Carbon Steel Wire Rope
M - High Carbon SteelP - Wire RopeAp - Oil and GasCd - Typical manufacturing
Cm - Nital Etched Micrography by OMDf - No Coating Layer

+12 more from this case →

ML00110 — Non Conformance in Spray and Fuse PinM - Low Alloy Medium Carbon QTP - Tubular ForgingAp - O&G Well DrillingCd - Heat Treatment Defect
ML00110 / Jan.2018
Non Conformance in Spray and Fuse Pin
M - Low Alloy Medium Carbon QTP - Tubular ForgingAp - O&G Well DrillingCd - Heat Treatment Defect
Cm - As polished micrographyDf - Surface Layer
ML00110 / Jan.2018
Non Conformance in Spray and Fuse Pin
M - Low Alloy Medium Carbon QTP - Tubular ForgingAp - O&G Well DrillingCd - Heat Treatment Defect
Cm - As polished micrographyDf - Surface Layer
ML00110 / Jan.2018
Non Conformance in Spray and Fuse Pin
M - Low Alloy Medium Carbon QTP - Tubular ForgingAp - O&G Well DrillingCd - Heat Treatment Defect
Cm - As polished micrographyDf - Low Mag
ML00110 / Jan.2018
Non Conformance in Spray and Fuse Pin
M - Low Alloy Medium Carbon QTP - Tubular ForgingAp - O&G Well DrillingCd - Heat Treatment Defect
Cm - Nital Etched Micrography by OMDf - Ferrite and Pearlite
ML00110 / Jan.2018
Non Conformance in Spray and Fuse Pin
M - Low Alloy Medium Carbon QTP - Tubular ForgingAp - O&G Well DrillingCd - Heat Treatment Defect
Cm - Nital Etched Micrography by OMDf - Base Metal

+5 more from this case →

ML00116 — CMn Steel Structural Tubing 6 mm thickM - CMn SteelP - Seamless Round ShapeAp - StructureCd - Removed From Service
ML00116 / Jan.2018
CMn Steel Structural Tubing 6 mm thick
M - CMn SteelP - Seamless Round ShapeAp - StructureCd - Removed From Service
Cm - Nital Etched Micrography by OMDf - Banded Structure
ML00116 / Jan.2018
CMn Steel Structural Tubing 6 mm thick
M - CMn SteelP - Seamless Round ShapeAp - StructureCd - Removed From Service
Cm - Nital Etched Micrography by OMDf - In the Center of the Thickness
ML00116 / Jan.2018
CMn Steel Structural Tubing 6 mm thick
M - CMn SteelP - Seamless Round ShapeAp - StructureCd - Removed From Service
Cm - Nital Etched Micrography by OMDf - Close to the External Surface
ML00116 / Jan.2018
CMn Steel Structural Tubing 6 mm thick
M - CMn SteelP - Seamless Round ShapeAp - StructureCd - Removed From Service
Cm - Nital Etched Micrography by OMDf - Close to the Internal Surface
ML00115 — CMn Steel Structural Tubing 5 mm thickM - CMn SteelP - Seamless Round ShapeAp - StructureCd - Removed From Service
ML00115 / Jan.2018
CMn Steel Structural Tubing 5 mm thick
M - CMn SteelP - Seamless Round ShapeAp - StructureCd - Removed From Service
Cm - Nital Etched Micrography by OMDf - Banded Structure
ML00115 / Jan.2018
CMn Steel Structural Tubing 5 mm thick
M - CMn SteelP - Seamless Round ShapeAp - StructureCd - Removed From Service
Cm - Nital Etched Micrography by OMDf - In the Center of the Thickness
ML00115 / Jan.2018
CMn Steel Structural Tubing 5 mm thick
M - CMn SteelP - Seamless Round ShapeAp - StructureCd - Removed From Service
Cm - Nital Etched Micrography by OMDf - Close to the External Surface
ML00115 / Jan.2018
CMn Steel Structural Tubing 5 mm thick
M - CMn SteelP - Seamless Round ShapeAp - StructureCd - Removed From Service
Cm - Nital Etched Micrography by OMDf - Close to the Internal Surface
ML00114 — CMn Steel Structural Tubing 8 mm thickM - CMn SteelP - Seamless Round ShapeAp - StructureCd - Removed From Service
ML00114 / Jan.2018
CMn Steel Structural Tubing 8 mm thick
M - CMn SteelP - Seamless Round ShapeAp - StructureCd - Removed From Service
Cm - Nital Etched Micrography by OMDf - Banded Structure
ML00114 / Jan.2018
CMn Steel Structural Tubing 8 mm thick
M - CMn SteelP - Seamless Round ShapeAp - StructureCd - Removed From Service
Cm - Nital Etched Micrography by OMDf - In the Center of the Thickness
ML00114 / Jan.2018
CMn Steel Structural Tubing 8 mm thick
M - CMn SteelP - Seamless Round ShapeAp - StructureCd - Removed From Service
Cm - Nital Etched Micrography by OMDf - Close to the External Surface
ML00114 / Jan.2018
CMn Steel Structural Tubing 8 mm thick
M - CMn SteelP - Seamless Round ShapeAp - StructureCd - Removed From Service
Cm - Nital Etched Micrography by OMDf - Close to the Internal Surface