hardness

Date 10-21-2010 11:06

I think it could go either way depending upon the heat input,the type of hardness test, and where in the HAZ you tested.
Without looking it up, since it isn't handy, I assume 252 is a larger grained material. So, if you used low heat input the HAZ will be normalized in which case you would realize more hardnss. If you used high heat input you would tend more towards annealing in which case it could be softer. If you used a MIC 10 you could end up in either types of zones. If you used a telebrineller and ground the weld to access the hte HAZ you would get a more homogeneous sample.
If you tested near the weld it would have a tendency to be different than the outer part of the HAZ.
NOTHING is more complicated than a HAZ.

By mohamed radwan (*)

Date 10-21-2010 11:20

thx but here is the results i got after i tested the hardness
the hardness of the material the basic metal was 99 HRB
the hardness of the HAZ is 96 HB
and in other spots were 76 HRB
can this be normal ?

By js55

Date 10-21-2010 14:56

IMO, I think your over thinking this. The 76 HRB is still going to be well over 60ksi tensile, though there is no direct conversion.
Therefore, I'd say that if your weld regime is normal and you have CMTR's on your material, its normal.
Your Rockwell could be all over the place depending upon where you are. Try something with a bigger sample.