Hello everyone,
I have this fractured copper alloy shaft that shows what looks to me as chevron marks pointing to a single iniciation site. On SEM examination the mode of fracture observed was ductile overload. I have always associated chevron marks to brittle fracture. Is it possible to see...
Hello everyone,
I would like to hear (read) your thoughts on the image I'm posting. It belongs to a 4140, 2" diameter steel bar . Notice the coarse acicular structure + fine pearlite grains (?). I was told by a material specialist that it corresponds to the absence of heat treatment after...
Hello everyone,
I'm currently dealing with a sample that belongs to a hydraulic quick coupling that had fracture after an external load was apllied due to a lateral pulling of the hose. CQ 0.19 C, 1.10 Mn, <0.0100 Si, 0.11 Cr, 0.195 Cu, 0.087 Ni, 0.028 Mo, [highlight #F57900]0.0965...
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we are trying to do the verification of a portable hardness tester acording to ASTM A956 Part B. "Verification of leeb hardness instruments by a standarized block method". The criterion given in 15.1 and 15.2 states that the instrument shall be considered verified if two...
Hello everyone, I want to know if someone can help me identify this mechanism of damage so I can look it up in the bibliography by its proper name.
Thank you.
(Reference in millimeters)
Hello everyone, I know that this issue has been discussed before but I need further help please. The thing is that it came to me a 36" diameter pressure vessel whose shell is made of a API 5L Gr. X70 welded pipe. I want to know if this material can be recertified as a material accepted by the...
Hello everyone,
During a inspection by replica technique in a 40 year old boiler, we got to these micrographs. The first one belongs to the corrugated furnace (seems like no microstructural degradation) and the second to a ring located in the mouth of the furnace. The client provided us a...
Hello everyone, I'm looking for some information about the type of failure and fracture surface appearance on this particular case: an sprocket shaft made of SAE 1144 (resulfurized steel) fails at de keyway showing long circunferential cracks in a way that makes me think that corresponds to a...
