Welding Tips and Tricks

Okay this is a curiosity question. I tried to find info but didn't come up with much. When or why would it be better to use the B2 over the D2. I figure there different chemical make up has to give properties that are more desirable in certain situations, but what advantages and disadvantages make these two fillers needed in the world.

I got these chemical compositions from the Harris site

ER80S-D2
-Si - 0.5-0.8%
-Mn - 1.6-2.1%
-P - 0.025%
-C - 0.07-0.12%
-Mo - 0.4-0.6%
-S - 0.025%
-Ni - 0.15%

ER80S-B2
-Si - 0.4-0.7%
-Mn - 0.4-0.7%
-Cr - 1.2-1.5%
-P - 0.025%
-C - 0.07-0.12%
-Mo - 0.4-0.6%
-S - 0.025%
-Ni - 0.2%

Biggest difference I see is the added Cr in the B2 mixture so does anyone have an idea on when to use this mix over the other. I realized this is kind of trivial to most people Thanks in advance if anyone has input on this

Are you welding CrMo by chance? Someone will chime in at some point, but the only time I've personally used ER80S-D2 is at school when welding 4130. Lincoln had a good article on welding CrMo where they talk about using ER70S2 I believe rather than the 80 due to the fact that they wanted the impact critical welds to fail before the part itself to absorb the impact (iirc. I could be way off on their reasoning its been a few months since I read it lol)

Your post got me curious and Googling I found some interesting info and opinions on these sites ;

http://www.millerwelds.com/resources/co ... oly-tubing

http://www.netwelding.com/Welding%204130.htm

http://www.rapidwelding.com/files/RA311650.pdf SD2

http://www.rapidwelding.com/dynamic/Cat ... &zl=3&sq=4 SB2

I've used the ER80S-D2, ( also pure 4130 and CMS 32 ) on 4130 and the ER80S-B2 ( as A32 ) when welding 25CrMo4 ( European equivalent, sort of, for 4130 ) to 1.7734 ( 15CDV6 ) which is a CrVa steel.

For 4130 I use ER70S2 the more experienced guys I know always said to use it do to elongation properties of It. Gives the joints ability to give some before stuff starts coming apart. I was just recently gonna start experimenting with some ER80S-D2 on some parts that the tensile strength would be more desirable and noticed this ER80S-B2 never hear about it and was wondering what purpose this filler would be good for. Not something I need but figured would be a good find out about might find a future use for it.