
Fig. 1a.
Example of a welded low-carbon steel etched with 2% nital showing the clear superiority of color etching in revealing the grain
structure. The as-cast weld metal is shown at the far left and the base metal
is shown at the far right, above the µm bar. In between, we see the heat-affected
zone starting with coarse irregular grains adjacent to the fusion line,
progressing to finer more uniformly shaped grains, then to columnar grains and
finally to the very fine-grained equiaxed ferrite grains in the base metal.

Fig. 1b.
Example of a welded low-carbon steel etched with Klemm’s I
showing the clear superiority of color etching in revealing the grain
structure. The as-cast weld metal is shown at the far left and the base metal
is shown at the far right, above the µm bar. In between, we see the heat-affected
zone starting with coarse irregular grains adjacent to the fusion line,
progressing to finer more uniformly shaped grains, then to columnar grains and
finally to the very fine-grained equiaxed ferrite grains in the base metal.
Recent Comments
definitions HT, passivate
Man Care
Brazing of 2205 Duplex Stainless Steel to 7020 & 5083 Aluminum alloy
grain boundary oxidization
Thanks to the Mike or Mikes!