Intergranular Cracking

27 cases · 60 images

Crevice Corrosion in a Subsea System — Aspect Before Analysis

Results

SortNewestOldestTitle A-ZTitle Z-A
Micrography perpendicular to the fracture surface showing, in the secondary cracks, the intergranular morphology of the fracture.
33
VIEW
ML00182 / Jul.2022
Brittle Fracture of a LAS Fixing Rod
M - Low Alloy Medium Carbon QTP - StemAp - Mechanical IndustryCd - Brittle Fracture
Cm - Nital Etched Micrography by OMDf - Intergranular Cracking
The intergranular morphology of the cracks, at the heat affected zone of the forging, indicates it is a cold cracking probably formed when the welded joint was not yet post welding heat treated. The actual hardness values at the HAZ is 270HV10, and when it was cracked it was probably a lot higher.
71
VIEW
ML00178 / Jan.2022
Cold cracks in Cr-Mo Welded Forging
M - CrMo SteelP - ForgingAp - O&G Well DrillingCd - Welding Defect
Cm - Nital Etched Micrography by SEMDf - Intergranular Cracking
Detailed microstructure of the heat affected zone, fully carburized and cracked intergranular. Large austenitic grain size.
19
VIEW
ML00174 / Jul.2021
Carburization of a 347 SS Welded Joint
M - Austenitic Stainless SteelP - Fabrication WeldAp - EnergyCd - Carburization
Cm - Oxalic Acid Electrolytic EtchDf - Intergranular Cracking
Micrographic aspect of the multiple intergranular cracks, initiating from the bottom of a pit.
25
VIEW
ML00172 / Mar.2021
Brittle Fracture of a LAS Valve Spring
M - Low Alloy Medium Carbon QTP - SpringAp - Oil and GasCd - Brittle Fracture
Cm - As polished micrographyDf - Intergranular Cracking
Micrography close to the external surface (to the top). The layer of intergranular corrosion shows evidences of selective leaching (suggesting that the aluminum was preferentially consumed). The stress corrosion cracking starts from the intergranularly corroded layer.
113
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 - Intergranular Cracking
SAMPLE 1, AT THE FRACTURE - Micrographic detail, as polished, of the oxides that are penetrating in the austenitic grain boundaries. The oxidation created intergranular cracks in regions close to the edge of the rectangular tube, that are more susceptible to suffer cyclic thermal stresses, since the furnace is weekly turned off, during two days.
55
VIEW
ML00160 / Apr.2020
High Temperature Degradation of 310SS
M - Austenitic Stainless SteelP - Rectangular TubeAp - Chemical IndustryCd - Scaling
Cm - As polished micrographyDf - Intergranular Cracking
Micrography of a longitudinal section of the bolt, in a position close to the fracture (top) and bolt surface (left ), presenting several secondary intergranular cracks.
57
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 - Intergranular Cracking
Micrographic detail of the intergranular cracks.
41
VIEW
ML00138 / Jun.2018
Liquid Metal Embrittlement of a HSLA Steel
M - High Strength Low AlloyP - Coated ProductAp - Mechanical IndustryCd - Liquid Metal Embrittlement
Cm - Nital Etched Micrography by OMDf - Intergranular Cracking

More from these cases

ML00178 — Cold cracks in Cr-Mo Welded ForgingM - CrMo SteelP - ForgingAp - O&G Well DrillingCd - Welding Defect
Detail of the cold cracking at the previous austenite grain boundary of the martensitic structure.
55
VIEW
ML00178 / Jan.2022
Cold cracks in Cr-Mo Welded Forging
M - CrMo SteelP - ForgingAp - O&G Well DrillingCd - Welding Defect
Cm - Nital Etched Micrography by SEMDf - Intergranular Cracking
Detail of the cold cracking at the previous austenite grain boundary of the martensitic structure.
59
VIEW
ML00178 / Jan.2022
Cold cracks in Cr-Mo Welded Forging
M - CrMo SteelP - ForgingAp - O&G Well DrillingCd - Welding Defect
Cm - Nital Etched Micrography by SEMDf - Intergranular Cracking
ML00172 — Brittle Fracture of a LAS Valve SpringM - Low Alloy Medium Carbon QTP - SpringAp - Oil and GasCd - Brittle Fracture
Micrographic detail of the intergranular cracks, initiating from the bottom of a pit.
29
VIEW
ML00172 / Mar.2021
Brittle Fracture of a LAS Valve Spring
M - Low Alloy Medium Carbon QTP - SpringAp - Oil and GasCd - Brittle Fracture
Cm - As polished micrographyDf - Intergranular Cracking
ML00139 — Hydrogen Fracture of a 17-4 PH Allen BoltM - Precipitation Hardened Stainless SteelP - Allen BoltAp - SubseaCd - Hydrogen Embrittlement
Micrographic detail of the secondary intergranular cracks close to the surface of the bolt, where the fracture occurred.
56
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 - Intergranular Cracking
Micrographic detail of the intergranular cracks in the transition between the threaded body and the head of the non broken bolt, indicating that this bolt was also embrittled and could fail soon.
48
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 - Intergranular Cracking
ML00138 — Liquid Metal Embrittlement of a HSLA SteelM - High Strength Low AlloyP - Coated ProductAp - Mechanical IndustryCd - Liquid Metal Embrittlement
Scanning electron fractography (originally 1000x), showing intergranular aspects in the fracture surface.
42
VIEW
ML00138 / Jun.2018
Liquid Metal Embrittlement of a HSLA Steel
M - High Strength Low AlloyP - Coated ProductAp - Mechanical IndustryCd - Liquid Metal Embrittlement
Cm - Fractography by SEMDf - Intergranular Cracking