Copper Alloy

5 cases · 79 images

Crevice Corrosion in a Subsea System — Aspect Before Analysis

Condition: Damage clear all

Copper Alloy — sub-branches

Aluminum Brass 1Aluminum Bronze 1Brass 2Pure Copper 1

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Aspect of the 3 1/2" diameter tube after the water leakage in high temperature.
962
VIEW
ML00180 / Mar.2022
Local Melting of Copper Cooling Tubes
M - Pure CopperP - Cooling TubeAp - SiderurgyCd - Overheating
Cm - Aspect Before AnalysisDf - General View
Visual aspect of the internal side of the tube, after longitudinal cut, presenting the region of leakage. The tube, that is 1.6mm thick, presented several points of localized diissolution .
457
VIEW
ML00170 / Sep.2020
MIC in Aluminum Brass Tubes
M - Aluminum BrassP - Seamless tubeAp - MaritimeCd - Preferential Dissolution
Cm - Surface AspectDf - Localized Thinning
Aspect "as received" of the seamless tube at the curved position, showing the longitudinal crack and corrosion products at the tube surface.
836
VIEW
ML00165 / Jul.2020
SCC of Aluminum Bronze Heating Coil
M - Aluminum BronzeP - Seamless tubeAp - Oil and GasCd - Stress Corrosion
Cm - Aspect Before AnalysisDf - General View
Aspect of the CuZn platesheet where it is corroded (cooling medium side). The (hot) air cooler uses treated seawater as the cooling medium and the corroded regions are associated to the regions in the heat exchanger of higher temperatures, and the leakage occurred in regions of contact of the platesheet to cooper alloy tubes.
1167
VIEW
ML00125 / Mar.2018
Dezincification of a Cooler Tubesheet
M - BrassP - PlateAp - ShipCd - Preferential Dissolution
Cm - Aspect Before AnalysisDf - Corrosion
The fracture micromechanism is ductile for the pin that has been sheared in a condition of controlling the load carrying. Elongated Dimples.
453
VIEW
ML00007 / Dec.2020
Free Machining Brass in Shear Pin
M - BrassP - Machined PartAp - LiftingCd - Shear
Cm - Fractography by SEMDf - Elongated Dimples

More from these cases

ML00180 — Local Melting of Copper Cooling TubesM - Pure CopperP - Cooling TubeAp - SiderurgyCd - Overheating
View of the iinternal side of the tube (water side), deformed in the overheated area. There are several leaking points.
115
VIEW
ML00180 / Mar.2022
Local Melting of Copper Cooling Tubes
M - Pure CopperP - Cooling TubeAp - SiderurgyCd - Overheating
Cm - Aspect Before AnalysisDf - Internal Surface
Macroscopic aspect after cutting longitudinally in two halfs, at the damaged area. The tube internal surface showed a red copper colour at the overheated region and the perforation is associated to longitudinal cracks.
104
VIEW
ML00180 / Mar.2022
Local Melting of Copper Cooling Tubes
M - Pure CopperP - Cooling TubeAp - SiderurgyCd - Overheating
Cm - Longitudinal Section AspectDf - Internal Surface
Detail of the perforation point, internal view. Aligned perforations in the overheated region and interconnected longitudinal cracks.
94
VIEW
ML00180 / Mar.2022
Local Melting of Copper Cooling Tubes
M - Pure CopperP - Cooling TubeAp - SiderurgyCd - Overheating
Cm - Longitudinal Section AspectDf - Leakage
Micrographic aspect of the tube out of the damaged region, in a longitudinal section, showing the grain refined copper structure.
96
VIEW
ML00180 / Mar.2022
Local Melting of Copper Cooling Tubes
M - Pure CopperP - Cooling TubeAp - SiderurgyCd - Overheating
Cm - FeCl3+HCl+H2O Etched MicroDf - In the Center of the Thickness
Micrographic detail of the granular copper structure, a little far from the overheated region.
102
VIEW
ML00180 / Mar.2022
Local Melting of Copper Cooling Tubes
M - Pure CopperP - Cooling TubeAp - SiderurgyCd - Overheating
Cm - FeCl3+HCl+H2O Etched MicroDf - Granular structure

+14 more from this case →

ML00170 — MIC in Aluminum Brass TubesM - Aluminum BrassP - Seamless tubeAp - MaritimeCd - Preferential Dissolution
Macrography of a transverse section of the tube close to the leakage point, evidencing a localized thinning from the internal side of the tube.
65
VIEW
ML00170 / Sep.2020
MIC in Aluminum Brass Tubes
M - Aluminum BrassP - Seamless tubeAp - MaritimeCd - Preferential Dissolution
Cm - Transverse Section AspectDf - Localized Thinning
Visual aspect of the internal side of the tube, after longitudinal cut, presenting regions where the internal layer is fully stained.
55
VIEW
ML00170 / Sep.2020
MIC in Aluminum Brass Tubes
M - Aluminum BrassP - Seamless tubeAp - MaritimeCd - Preferential Dissolution
Cm - Aspect Before AnalysisDf - Internal Surface
Detailed aspect, by a low magnification microscope, of the internal side of the tube, after longitudinal cut. The tube, that is 1.6mm thick, presented several points of localized corrosion leading to leaks.
46
VIEW
ML00170 / Sep.2020
MIC in Aluminum Brass Tubes
M - Aluminum BrassP - Seamless tubeAp - MaritimeCd - Preferential Dissolution
Cm - Surface AspectDf - Localized Corrosion
Uniform granular microstructure of the aluminum brass, monophasic alpha.
44
VIEW
ML00170 / Sep.2020
MIC in Aluminum Brass Tubes
M - Aluminum BrassP - Seamless tubeAp - MaritimeCd - Preferential Dissolution
Cm - FeCl3+HCl+Ethanol Etched MicroDf - Alpha
Micrographic detail of the granular structure of the aluminum brass, monophasic alpha.
44
VIEW
ML00170 / Sep.2020
MIC in Aluminum Brass Tubes
M - Aluminum BrassP - Seamless tubeAp - MaritimeCd - Preferential Dissolution
Cm - FeCl3+HCl+Ethanol Etched MicroDf - Alpha

+10 more from this case →

ML00165 — SCC of Aluminum Bronze Heating CoilM - Aluminum BronzeP - Seamless tubeAp - Oil and GasCd - Stress Corrosion
Aspect of the external tube surface after cleaning. It is possible to see that the cracks are longitudinal to the tube and localized in positions where the surface is corroded.
132
VIEW
ML00165 / Jul.2020
SCC of Aluminum Bronze Heating Coil
M - Aluminum BronzeP - Seamless tubeAp - Oil and GasCd - Stress Corrosion
Cm - Surface AspectDf - External Surface
Aspect of the internal tube surface after a longitudinal cut, without cleaning. It is possible to see a clean surface inside the tube.
104
VIEW
ML00165 / Jul.2020
SCC of Aluminum Bronze Heating Coil
M - Aluminum BronzeP - Seamless tubeAp - Oil and GasCd - Stress Corrosion
Cm - Surface AspectDf - Internal Surface
Micrography of the tranverse section of the tube, in the center of the thickness. There are small grains and large grains, characterizing a dual grain size. The large grains size is about 100 microns, more than 10 times larger than the average size of the smaller grains size.
101
VIEW
ML00165 / Jul.2020
SCC of Aluminum Bronze Heating Coil
M - Aluminum BronzeP - Seamless tubeAp - Oil and GasCd - Stress Corrosion
Cm - FeCl3+HCl+H2O Etched MicroDf - Dual grain sizes
Micrographic detail of the alpha microstructure presenting dual grain sizes. Two different types of twins are presented in the structure: annealing twins and deformation twins, suggesting that the material was probably partially recristalized after cold deformation and stress relief treatment.
87
VIEW
ML00165 / Jul.2020
SCC of Aluminum Bronze Heating Coil
M - Aluminum BronzeP - Seamless tubeAp - Oil and GasCd - Stress Corrosion
Cm - FeCl3+HCl+H2O Etched MicroDf - Alpha
Micrography of a transverse section of the bent tube, external surface (OD) to the top and internal surface (ID) to the bottom of the figure. At the through wall cracking position, the external surface presented a layer of intergranular corrosion.
95
VIEW
ML00165 / Jul.2020
SCC of Aluminum Bronze Heating Coil
M - Aluminum BronzeP - Seamless tubeAp - Oil and GasCd - Stress Corrosion
Cm - As polished micrographyDf - Cracking

+12 more from this case →

ML00125 — Dezincification of a Cooler TubesheetM - BrassP - PlateAp - ShipCd - Preferential Dissolution
Micrography of a transverse section of the platesheet presenting a duplex structure, alpha (light yellow) and beta (orange) phases.
214
VIEW
ML00125 / Mar.2018
Dezincification of a Cooler Tubesheet
M - BrassP - PlateAp - ShipCd - Preferential Dissolution
Cm - FeCl3+HCl+Ethanol Etched MicroDf - Alpha and Beta
Aspect of the tubesheet after removal of the cooper alloy tubes and water cleaning. The corrosion is more intense in the regions of tube connection.
176
VIEW
ML00125 / Mar.2018
Dezincification of a Cooler Tubesheet
M - BrassP - PlateAp - ShipCd - Preferential Dissolution
Cm - Surface AspectDf - Corrosion
Transverse section of the tubesheet, after removal of the tubes. The seawater sie is to the top of the figure. It is possible to see regions of localized corrosion close to the tube position and a red layer all through the plate surface.
182
VIEW
ML00125 / Mar.2018
Dezincification of a Cooler Tubesheet
M - BrassP - PlateAp - ShipCd - Preferential Dissolution
Cm - Transverse Section AspectDf - Corrosion
Macrographic detail of the transverse section of the tubesheet at the cooper alloy tube position, after removal of the 5/8" tube. The red layer at the top of the plate (exposed to the cooling medium - treated seawater) is a region of selective corrosion, dezincification.
169
VIEW
ML00125 / Mar.2018
Dezincification of a Cooler Tubesheet
M - BrassP - PlateAp - ShipCd - Preferential Dissolution
Cm - Transverse Section AspectDf - Corrosion
Macrographic detail of the transverse section of the tubesheet at the cooper alloy tube position, after removal of the 5/8" tube. The "layer" at the top of the plate (exposed to the cooling medium - treated seawater) is a region of selective corrosion, dezincification. It is possible to see that in the right side of the figure, where the cooper tube was positioned, the corrosion damage is deeper.
153
VIEW
ML00125 / Mar.2018
Dezincification of a Cooler Tubesheet
M - BrassP - PlateAp - ShipCd - Preferential Dissolution
Cm - Transverse Section AspectDf - Dezincification

+13 more from this case →

ML00007 — Free Machining Brass in Shear PinM - BrassP - Machined PartAp - LiftingCd - Shear
Uniform structure of the 1" shear pin all through the section. The edge is the fracture surface.
108
VIEW
ML00007 / Dec.2020
Free Machining Brass in Shear Pin
M - BrassP - Machined PartAp - LiftingCd - Shear
Cm - FeCl3+HCl+H2O solution Etched MacroDf - Longitudinal Section
The fracture surface is flat and smashed due to the shearing action.
87
VIEW
ML00007 / Dec.2020
Free Machining Brass in Shear Pin
M - BrassP - Machined PartAp - LiftingCd - Shear
Cm - Aspect Before AnalysisDf - Fracture
The fracture surface is ductile and the micromechanism is dimples, elongated due to the shearing action.
83
VIEW
ML00007 / Dec.2020
Free Machining Brass in Shear Pin
M - BrassP - Machined PartAp - LiftingCd - Shear
Cm - Fractography by SEMDf - Ductile Fracture
The micrography of the pin far from the fracture surface shows a biphasic brass, and Pb inclusions that are intentional to give a free machining condition for the alloy.
76
VIEW
ML00007 / Dec.2020
Free Machining Brass in Shear Pin
M - BrassP - Machined PartAp - LiftingCd - Shear
Cm - FeCl3+HCl+H2O Etched MicroDf - Two phases
The micrography of the pin at the fracture surface shows a strong plastic deformation as expected during shearing.
69
VIEW
ML00007 / Dec.2020
Free Machining Brass in Shear Pin
M - BrassP - Machined PartAp - LiftingCd - Shear
Cm - FeCl3+HCl+H2O Etched MicroDf - Plastic Deformation