So would I, but the hardnesses reported to me have been:
Lowest - 127 BHN
Highest - 223 BHN
Most between 150 and 190
I can't figure it out. The PWHT chart they supplied looks reasonable - if it is the right one. The hardnesses are ridiculous for the material and PWHT described - if they took...
Was the reported bainite in the base metal, weld metal or HAZ; --- all
through thickness or OD surface? --- od
How was preheating and dehydrogenation performed; with resistance elements or oxy-acetylene? --- resistance
Thermal history : Preheat to 400F, Weld, Post heat @ 625F for 2 hr, cool...
Thanks! I suspect they don't know what they are looking at as metenge suggests. It is frustrating not to have access to this to see for myself. Looking at the PWHT charts (exceptionally slow cooling rate) and hardness reading (low), they probably have martensite + ferrite + carbides.
Would someone explain to me how P-91, welded to F-91 with 91 filler could turn into bainite. I have never seen any studies, or CCT diagrams saying it could be anything but martensite (possibly with retained austenite), even after PWHT. It was reported bainite microstructure. All I could think...
