There are two main groups of electrodes for welding cast iron; machinable
Machinable type are those whose deposits are soft and ductile enough so they
can easily be machined after welding. They are used to repair all kinds of
broken castings, correcting for machine errors, filling up defects, or to
weld cast iron to steel.
There are two common types of machinable electrodes. Characteristics of
these AWS classification electrodes are as follows: ( classification based
on chemical composition of metal involved. The suffix CI designates an
electrode for cast iron).
ENi-CI - Nickel Electrode
DCR or AC, general purpose
welding especially for thin and medium sections, and casting with low
phosphorus content, and where little or no preheat is used.
ENi-FeCI - Nickle Iron Electrode
DCR or AC for welding heavy
sections, high phosphorus castings, high nickle alloy castings where
high-strength welds are required. and welding nodular iron.
This is from THOMAS' Wrought Iron Works in Saskatoon, Sk, Canada or
I think there is a problem of what material we are refering to in the
"cast steel" is a very unfortunate name, as it doesn't mean much in
the current context. "cast steel" refers to steel with about 0.8% to
1% Carbon. That is, it is a steel which can be quench-hardened to
give very sharp edges like chisels and so on. It would be
mass-produced in an electric arc furnace and is no more "cast" then
any other steel, be it sheet, plate, billet, rail, etc.
So nothing to do with "cast iron".
Historically, the name "cast steel" came about in the late 1700's and
1800's because the steel was made in crucibles (with charcoal
additions) then cast into little ingots which were forged to scythes
and the like. The other "steel" of the time was wrought-iron, which
was never molten as steel, being reduced to a spongy solid then forged
("wrought") to squeeze out the slag. Wrought iron could be
case-carburised giving "blister steel", which was used to make cutting
edges, though the homogenous hardenability of crucible steel was
advantageous for mass-production.
Look-up the Huntsman crucible process for making tool steel. I come
from Sheffield where this stuff started-out.
Welding - your question could be rephrased as "how do I weld a
hardenable high-carbon steel to a mild steel?"
I'll duck-out here, as there are others much more expert than me. In
general though, you have to avoid high hardnesses and hydrogen
cracking. When I have been confronted with this situation, I preheat
to 'til there are colour patinas showing on the metal (it must be over
200C (392F)), use a low-hydrogen welding process like (solid-wire,
"tradional") MIG then put the weldment in an oven for a few hours to
reduce the hydrogen level. Has worked for me in the few instances I
have welded high-carbon steel.
Oh yeah -- other trick - never tried it, but a familiar technique -
weld using an austenic stainless steel electrode. The weld hydrogen
has high solubility and low mobility in the austenitic stainless
steel, so what hydrogen does make it into the heat-affected-zone of
the parent material is wicked-away relatively extremely fast and the
concentrations of hydrogen are very low. All cracking in the weld
zone is "hydrogen cracking", it is reckoned. Take away hydrogen and
you won't get cracking, however hard the structures you form. This is
the trick which caused the Nazi German forces sweeping across Russia
to suddenly encounter a huge onslaught of these indigenous Russian
tanks better than anything they had - the Russians discovered you
could weld armour plate (highly hardenable and cracking-susceptible)
with austenitic stainless steel electrodes. OK, the Nazi Germans
responded with a better tank (a bit better), but it took something
like four times as much effort to build and in the brutality of war
they were swamped and everyone there found themselves with a one-way
Well, I am confused......... so let me ramble on a bit. I put air suspension
(Volvo semi) on an 84 GMC school bus. The ride has been improved vastly, but
there is a bit of sway now. To correct the sway I would like to add a .....sway
bar..... Got one from the salvage yard. The ends that attach to the axle are
cast.....Cast steel maybe? They were cast in the shape of a spring pad, they go
between the leaf spring of the original vehicle and the axle housing. What I
would like to do is cut these ends a little and weld them to a hunk of steel
that would be bolted-via the rear suspension u-bolts-to the under side of the
So, can these two types of metal be welded and have the necessairy strength to
withstand the stress seen by heavy duty suspension components?
I apologize for not being clearer in my original post. But, as a novice, it is
hard to know how much information is enough and not too much.
Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here.
All logos and trade names are the property of their respective owners.