Inclusion Chemistry and Morphology in Shielded Metal Arc (SMA) Steel Weld Deposits

The composition and morphology, and the size and distribution of the nonmetallic inclusions found within a series of shielded metal arc (SMA), C-Mn steel weld deposits, produced using AWS E7016 type electrodes, have been investigated using transmission electron microscopy (TEM) and associated x-ray microanalysis techniques. The majority of the inclusions were ≈ 0.1 μm to ≈ 1.0 μm in diameter, and microanalysis generally showed them to be rich in Mn, Si, and Ti, with lower levels of Al, Cu, and S. Most of the inclusions were heterogeneous, often containing Mn- or Cu-rich sulphide globules embedded in their surfaces.