Optical Microscope

8 cases · 14 images

Crevice Corrosion in a Subsea System — Aspect Before Analysis

Low magnification micrography, by optical microscope, of the longitudinal section of a damaged bolt, in the center of the thickness. The microstructure is austenitic, free from carbides.
100
ML00157 / Feb.2020
Bolts Under Chloride SCC Conditions
M - Austenitic Stainless SteelP - BoltAp - Oil and GasCd - Stress Corrosion
Cm - Oxalic Acid Electrolytic EtchDf - Austenite
Nitronic 60 cylinder. Micrography of the longitudinal section in the center of the thickness, presenting a fully austenitic microstructure, equiaxial grains, and evidences of the manufacturing process by hot forming.
179
ML00121 / Feb.2018
Pitting Corrosion in a Subsea System
M - Austenitic / MartensiticP - Rod & CylinderAp - SubseaCd - Pitting Corrosion
Cm - Micrography by OM using A262 Method ADf - Austenite
Micrography of the 1.65 mm thickness tube, in the middle of the thickness of the longitudinal section.  This part of the tube is located in the colder part of the equipment, position 1.  The material presented carbide precipitation at grain boundaries (not yet fully surrounding the grains) and at this point the tube presented no internal corrosion.
338
ML00086 / Nov.2017
Intergranular Corrosion of Sensitized 304SS
M - Austenitic Stainless SteelP - Seamless tubeAp - Heat ExchangerCd - Intergranular Corrosion
Cm - Micrography by OM using A262 Method ADf - Austenite
The shell plate micrography showed an austenitic structure.
101
ML00050 / Nov.2017
Fatigue Failure of a 316SS Pressure Stabilizer
M - Austenitic Stainless SteelP - Fabrication WeldAp - Chemical IndustryCd - Mechanical Fatigue
Cm - Micrography by OM using A262 Method ADf - Austenite
ML00041 / Jun.2017
Fatigue Fracture of Inconel 718 Spline Shaft
M - NiCrFe AlloyP - ShaftAp - Oil and GasCd - Vibration Induced Fatigue
Cm - Kalling Etched Micrography by OMDf - Austenite
Longitudinal section of the main pipe showing as austenitic structure with small amount of delta ferrite, aligned. The white band in the center of the figure is a segregation band that was not fully etched.
133
ML00006 / Apr.2017
Vibration Induced Fatigue in 304SS
M - Austenitic Stainless SteelP - Longitudinal Seam Welded PipeAp - PipingCd - Vibration Induced Fatigue
Cm - Micrography by OM using A262 Method ADf - Austenite
Microstructure of the fitting in the transverse section, presenting a granular Ni austenitic structure.  No evidences of any phase in the grain boundaries.
114
ML00011 / Oct.2017
Intergranular SCC of Pure Nickel
M - Unalloyed NickelP - Wrought FittingAp - Chemical IndustryCd - Stress Corrosion
Cm - Kalling Etched Micrography by OMDf - Austenite
Austenitic structure at the transverse section of the pipe, free from carbides.
277
ML00014 / Apr.2017
Pitting Corrosion in 316SS Pipe
M - Austenitic Stainless SteelP - Seamless PipeAp - FPSOCd - Pitting Corrosion
Cm - Micrography by OM using A262 Method ADf - Austenite

More from these cases

ML00121 — Pitting Corrosion in a Subsea SystemM - Austenitic / MartensiticP - Rod & CylinderAp - SubseaCd - Pitting Corrosion
Nitronic 60 cylinder. Micrography of the longitudinal section in the center of the thickness, presenting a fully austenitic microstructure, with some aligned non metallic inclusions.
157
ML00121 / Feb.2018
Pitting Corrosion in a Subsea System
M - Austenitic / MartensiticP - Rod & CylinderAp - SubseaCd - Pitting Corrosion
Cm - Micrography by OM using A262 Method ADf - Austenite
Nitronic 60 cylinder. Micrographic detail of the longitudinal section in the center of the thickness, presenting a fully austenitic microstructure, equiaxial grains, typical of a solution annealed condition.
136
ML00121 / Feb.2018
Pitting Corrosion in a Subsea System
M - Austenitic / MartensiticP - Rod & CylinderAp - SubseaCd - Pitting Corrosion
Cm - Micrography by OM using A262 Method ADf - Austenite
ML00006 — Vibration Induced Fatigue in 304SSM - Austenitic Stainless SteelP - Longitudinal Seam Welded PipeAp - PipingCd - Vibration Induced Fatigue
Longitudinal section of the main pipe showing as austenitic structure with small amount of delta ferrite, aligned (black dots).
117
ML00006 / Apr.2017
Vibration Induced Fatigue in 304SS
M - Austenitic Stainless SteelP - Longitudinal Seam Welded PipeAp - PipingCd - Vibration Induced Fatigue
Cm - Micrography by OM using A262 Method ADf - Austenite
ML00011 — Intergranular SCC of Pure NickelM - Unalloyed NickelP - Wrought FittingAp - Chemical IndustryCd - Stress Corrosion
Microstructure of the fitting in the transverse section, presenting a granular Ni austenitic structure.  No evidences of any phase in the grain boundaries.
110
ML00011 / Oct.2017
Intergranular SCC of Pure Nickel
M - Unalloyed NickelP - Wrought FittingAp - Chemical IndustryCd - Stress Corrosion
Cm - Kalling Etched Micrography by OMDf - Austenite
ML00011 / Oct.2017
Intergranular SCC of Pure Nickel
M - Unalloyed NickelP - Wrought FittingAp - Chemical IndustryCd - Stress Corrosion
Cm - Kalling Etched Micrography by OMDf - Austenite
ML00014 — Pitting Corrosion in 316SS PipeM - Austenitic Stainless SteelP - Seamless PipeAp - FPSOCd - Pitting Corrosion
Austenitic structure, free from carbides, exactly in the region of the pitting, indicating that the corrosion is not associated to the material microstructure.
261
ML00014 / Apr.2017
Pitting Corrosion in 316SS Pipe
M - Austenitic Stainless SteelP - Seamless PipeAp - FPSOCd - Pitting Corrosion
Cm - Micrography by OM using A262 Method ADf - Austenite