Optical Microscope

2 cases · 17 images

Crevice Corrosion in a Subsea System — Aspect Before Analysis

Condition: Hydrogen Standard: ASTM Detail focus: Sampling and Analysis clear all

Optical Microscope — sub-branches

As polished micrography 1Kalling Etched Micrography by OM 4Kroll Etched Micrography by OM 7Micrography by OM 5

Results

SortNewestOldestTitle A-ZTitle Z-A
Low magnification micrography transverse to the fillet weld in the pipe. The pipe base metal is to the bottom of the figure and the weld metal is to the top. The heat affected zone in the middle, shows a coarse grain size structure.
60
VIEW
ML00179 / Feb.2022
Hydrides in Titanium Weld
M - Unalloyed TitaniumP - In Field WeldAp - Chemical IndustryCd - Hydride Formation
Cm - Kroll Etched Micrography by OMDf - Welded Joint
Micrography of a longitudinal section, in the center, of the broken 5/8" bolt, presenting an aged martensitic structure. There are vertical "lines" that correspond to segregation bands due to the forming direction. These bands are evident only using low magnification microscopy.
168
VIEW
ML00139 / Jun.2018
Hydrogen Fracture of a 17-4 PH Allen Bolt
M - Precipitation Hardened Stainless SteelP - Allen BoltAp - SubseaCd - Hydrogen Embrittlement
Cm - Kalling Etched Micrography by OMDf - Longitudinal Section

More from these cases

ML00179 — Hydrides in Titanium WeldM - Unalloyed TitaniumP - In Field WeldAp - Chemical IndustryCd - Hydride Formation
Low magnification micrography showing the weld metal, full of pores, indicating that the field welding was not properly shileded.
50
VIEW
ML00179 / Feb.2022
Hydrides in Titanium Weld
M - Unalloyed TitaniumP - In Field WeldAp - Chemical IndustryCd - Hydride Formation
Cm - Kroll Etched Micrography by OMDf - Weld Metal
Coarse grains in the heat affected zone.
46
VIEW
ML00179 / Feb.2022
Hydrides in Titanium Weld
M - Unalloyed TitaniumP - In Field WeldAp - Chemical IndustryCd - Hydride Formation
Cm - Kroll Etched Micrography by OMDf - Heat Affected Zone
Micrography of the weld metal at the fillet weld where the cracking started, showing several brittle microcracks that corresponds to the regions where the fractography showed secondary crackis.
35
VIEW
ML00179 / Feb.2022
Hydrides in Titanium Weld
M - Unalloyed TitaniumP - In Field WeldAp - Chemical IndustryCd - Hydride Formation
Cm - Kroll Etched Micrography by OMDf - Weld Metal
Micrographic detail of the weld metal brittle microcracks, in regions with hydrides formation.
32
VIEW
ML00179 / Feb.2022
Hydrides in Titanium Weld
M - Unalloyed TitaniumP - In Field WeldAp - Chemical IndustryCd - Hydride Formation
Cm - Kroll Etched Micrography by OMDf - Weld Metal
Brittle crack in the surface of the welded joint, at the heat affected zone close to the fusion line.
31
VIEW
ML00179 / Feb.2022
Hydrides in Titanium Weld
M - Unalloyed TitaniumP - In Field WeldAp - Chemical IndustryCd - Hydride Formation
Cm - Kroll Etched Micrography by OMDf - Heat Affected Zone

+6 more from this case →

ML00139 — Hydrogen Fracture of a 17-4 PH Allen BoltM - Precipitation Hardened Stainless SteelP - Allen BoltAp - SubseaCd - Hydrogen Embrittlement
Micrography of a longitudinal section of the 5/8" bolt, at the bottom of the thread, presenting a refined structure compared to the center of the bolt and a mark at the thread flank that was probably created during tightening of the bolt.
95
VIEW
ML00139 / Jun.2018
Hydrogen Fracture of a 17-4 PH Allen Bolt
M - Precipitation Hardened Stainless SteelP - Allen BoltAp - SubseaCd - Hydrogen Embrittlement
Cm - Kalling Etched Micrography by OMDf - Longitudinal Section
Micrography of a longitudinal section of the bolt, close to the fracture surface (top of the figure), The fracture started at the surface (left side) in a position close to the bolt body to bolt head transition.
58
VIEW
ML00139 / Jun.2018
Hydrogen Fracture of a 17-4 PH Allen Bolt
M - Precipitation Hardened Stainless SteelP - Allen BoltAp - SubseaCd - Hydrogen Embrittlement
Cm - As polished micrographyDf - Longitudinal Section
Micrography of a longitudinal section, in the center of a non-broken bolt that operated in the same assembling, presenting an aged martensitic structure, similar to the broken bolt.
41
VIEW
ML00139 / Jun.2018
Hydrogen Fracture of a 17-4 PH Allen Bolt
M - Precipitation Hardened Stainless SteelP - Allen BoltAp - SubseaCd - Hydrogen Embrittlement
Cm - Kalling Etched Micrography by OMDf - Longitudinal Section
Micrography of a longitudinal section of the non-broken 5/8" bolt, at the transition between the threaded body and the head, showing a variation in the grain size (of the previous austenite) and evidences of a deformed structure at this transition.
41
VIEW
ML00139 / Jun.2018
Hydrogen Fracture of a 17-4 PH Allen Bolt
M - Precipitation Hardened Stainless SteelP - Allen BoltAp - SubseaCd - Hydrogen Embrittlement
Cm - Kalling Etched Micrography by OMDf - Longitudinal Section