I wanted some c clamps to mig weld to a steel plate, I got some clamps
that say pearlitic on them and the person I bought them from said
they're steel and weldable. I know cast can be welded to steel but don't
have the know how to do it and just want to deal with steel to steel,
what is this stuff called pearlitic, is it really steel?

Thanks,
Rudy

Rudolf Moehs wrote:
I wanted some c clamps to mig weld to a steel plate, I got some clamps
that say pearlitic on them and the person I bought them from said
they're steel and weldable. I know cast can be welded to steel but
don't have the know how to do it and just want to deal with steel to
steel, what is this stuff called pearlitic, is it really steel?

Thanks,
Rudy

No idea about the pearlitic thing but to weld steel to cast iron a stainless
rod works wonders.

Ken.

"Rudolf Moehs" wrote in
message
...
I wanted some c clamps to mig weld to a steel
plate, I got some clamps
that say pearlitic on them and the person I
bought them from said
they're steel and weldable. I know cast can be
welded to steel but don't
have the know how to do it and just want to deal
with steel to steel,
what is this stuff called pearlitic, is it
really steel?

Thanks,
Rudy

From an old university text book that I haven't
opened for about 30 years, it appears that
pearlite is a form of steel formed by slow
cooling. It is more ductile and less brittle than
martensite which is formed on quick cooling. I'd
guess that it will weld OK, but pack some
insulation around it after welding and let it cool
slowly.

Tom

Rudolf Moehs wrote:
I wanted some c clamps to mig weld to a steel plate, I got some clamps
that say pearlitic on them and the person I bought them from said
they're steel and weldable. I know cast can be welded to steel but don't
have the know how to do it and just want to deal with steel to steel,
what is this stuff called pearlitic, is it really steel?

Thanks,
Rudy

Hi Rudy,

It's a while since I studied any material science, but I'll have a go at
answering. I've just been reading some of this up in my materials book,
so if anyone spots a mistake in what I've said, please point it out.
Pearlite is a natural composite of ferrite and iron carbide, which are
two "phases" found in mixtures of iron and carbon which have been melted
and then cooled. All steel and cast iron which has been cooled slowly
from molten (i.e., not heat treated) will contain some pearlite. If a
mixture of iron and carbon which contains 0.80% carbon by weight is
cooled slowly, it will turn into pure pearlite. So if your clamps are
pure pearlite they will contain 0.80% carbon, and someone here can
probably provide advice on how easy they will be to weld. If your clamps
aren't pure pearlite then the name doesn't really tell you anything
useful about the steel.

Hope this helps.

Chris

From what I can tell if the clamps are pearlite then they are a relatively
high carbon steel. When you weld them and the weld cools there will be some
very brittle and hard martensite forming.
I would preheat the pieces to at least 300 F then weld and cover with
some sort of insulation to slow the cooling process.
Pearlite refers to the grain structure. Pearlite forms when relatively high
carbon steel ( 0.8 %) cools slowly such as when you anneal a steel. I found
a listing of 125,000 to 150,000 psi tensile strength. 0.9 percent carbon
steel is used for cold chisels and center punches so you can understand that
the weld area will be very brittle if you cool the weld area too quickly.
Using stainless welding rod as suggested reduces the chance of brittle
fracture when cooling. The nickel and chromium are what helps. The parent
material next to the weld that was not alloyed is still at risk.
The best way is "belt and suspenders" Preheat, use stainless or ni-rod
electrode and cool slowly.
Randy

"Rudolf Moehs" wrote in message

m...
I wanted some c clamps to mig weld to a steel plate, I got some clamps
that say pearlitic on them and the person I bought them from said
they're steel and weldable. I know cast can be welded to steel but don't
have the know how to do it and just want to deal with steel to steel,
what is this stuff called pearlitic, is it really steel?

Thanks,
Rudy

Are you sure you want to mig them. Other people seem to be
reccomending stainless steel rod and I think these are only available
for stick or tig.

I think Pearlite is cast iron that has been heated long enough for the
graphite to separate out and form into either layers (like
mother-of-pearl) or little balls. Usually it is called Malleable or
Ductile iron. I've been told to use nickel or type 312 stainless for
steel-to-whatever arc welds but they are expensive and hard to find as
MIG wire.

jw

Thanks for all your responses, thank god for epoxy, since there won't
be any load on the clamps except compression I think I'll just glue
them in place.

thanks again, Rudy

Rudy wrote:
Thanks for all your responses, thank god for epoxy, since there won't
be any load on the clamps except compression I think I'll just glue
them in place.

thanks again, Rudy

I wouldn't use epoxy. I don't think it will hold up very well. If you
aren't confident about welding them, you could make some kind of bracket
which goes around the frame of the C-clamp and clamps it to whatever
you're making. Granted, it's more work, but it'll be much stronger. If
the clamps aren't under a high load you could consider drilling bolt
holes in the frame of the clamp, but this isn't such a nice solution.
What size are the clamps and what is the project?

Best wishes,

Chris

My guess is that they are pearlitic malleable iron or pearlitic ductile
iron, neither of which is especially weldable. I never know of anyone
promoting steel as being pearlitic because usually in a steel if more
strength is desired a heat treat is done and the steel microstructure is
made to be martensitic.

Cast irons can be welded but often people find the Heat Affected Zone (HAZ)
to be objectionable because the carbon available from the graphite goes into
solution and when the molten weld deposit cools rapidly due to the heat sink
effect of the parts, ledeburite (iron carbide) will form which causes
machinability problems and hard structures where cracks may initiate if used
in tension.

Mark



"Rudolf Moehs" wrote in message
...
I wanted some c clamps to mig weld to a steel plate, I got some clamps
that say pearlitic on them and the person I bought them from said
they're steel and weldable. I know cast can be welded to steel but don't
have the know how to do it and just want to deal with steel to steel,
what is this stuff called pearlitic, is it really steel?

Thanks,
Rudy