One side of a stick welded joint shows a large ferrite grain structure not seen on a Sub Arc weld of the same metals. EDS analysis shows little variation in chemistry, hardness of ferrite grains is 112HV5. The cap half of the weld is a Sub Arc weld and it does not show the same structural variation. I have no information on welding procedures or materials/weld metal type. But would be interested in the cause of the band
HAZ may be composed of several subzones when the closest to fusion zone one is partially melted subzone (1) then there is coarse-grained overheated zone (2) , normalization subzone (3) , recrystallization subzone (4). Overheating results in the austenite grain growth. Later on cooling the allotriomorphic ferrite stars growing thus enriching the austenite by carbon and provoking bainitic reaction.
We can see from the figure above that no bainite has formed so that the HAZ fully consists of ferrite and may be residual austenite while further to the base metal there is pearlite.
Fusion zone contains 1.6% Cr (analysis 1), large grain 2 - 0.3%Cr (analysis 2) and zone 3 - 0,147% Cr (analysis 3). I would suggest that the large bright grain 2 is the austenite grain while darker ones might be ferrite with higher chromium content.
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