"Martin H. Eastburn" wrote in message
...
Explosive welding.
Simple as that.
Martin

N_Cook wrote:
Interesting , but no further forward. Looks as though these froststats
will
remain froststats. Surprising ping and bounce as much as six inches on
change of state, the loud ping is somewhat damped when inside the casing.
Need freezer spray to change the state of these discs (hysteresis and all
that). When back to body temp I tried grinding a spot in the centre of
the
concave side, no change in set temp. Tried 4 diametrical marks on the
concave side , no change in response. Tried deeper but small 8 cuts just
on
the perphery, now no ping but slowly migrates from one state to the other
,
still requiring freezer spray. I wonder how they "weld" these 2 materials
together.


(sorry for the digression.)
huh! yesterday i was going to ask how they make copper clad stainless steel
cookware but i thought it was too dumb and too trivial a question to ask.
couple days ago i had a copper clad stainless pan delaminate the copper
cladding and was stunned. made me wonder how they attach it in the first
place. i'm guessing some sort of furnace brazing process(?). this pan is
probably over 50 years old, i think this is one of the pans my mother got as
a wedding present in the 50's. i've seen stuff (on tv and in books) about
explosive welding but am totally assuming that's NOT how they make copper
clad cookware.

http://www.frontiernet.net/~wwixon/delamination.jpg

b.w.

"William Wixon" wrote in message
...

huh! yesterday i was going to ask how they make copper clad stainless
steel
cookware but i thought it was too dumb and too trivial a question to ask.
couple days ago i had a copper clad stainless pan delaminate the copper
cladding and was stunned. made me wonder how they attach it in the first
place. i'm guessing some sort of furnace brazing process(?). this pan is
probably over 50 years old, i think this is one of the pans my mother got
as
a wedding present in the 50's. i've seen stuff (on tv and in books) about
explosive welding but am totally assuming that's NOT how they make copper
clad cookware.

http://www.frontiernet.net/~wwixon/delamination.jpg



That is really wild. I have never heard of these delaminating. Was there
something you did like overheat the pot or something?

--

Roger Shoaf

About the time I had mastered getting the toothpaste back in the tube, then
they come up with this striped stuff.

"William Wixon" wrote in message
...
(sorry for the digression.)
huh! yesterday i was going to ask how they make copper clad stainless
steel
cookware but i thought it was too dumb and too trivial a question to ask.
couple days ago i had a copper clad stainless pan delaminate the copper
cladding and was stunned. made me wonder how they attach it in the first
place. i'm guessing some sort of furnace brazing process(?). this pan is
probably over 50 years old, i think this is one of the pans my mother got
as
a wedding present in the 50's. i've seen stuff (on tv and in books) about
explosive welding but am totally assuming that's NOT how they make copper
clad cookware.

http://www.frontiernet.net/~wwixon/delamination.jpg

b.w.


Here is how:
http://www.patentstorm.us/patents/41...scription.html

"Roger Shoaf" wrote in message
...



That is really wild. I have never heard of these delaminating. Was there
something you did like overheat the pot or something?

--

Roger Shoaf


probably in it's 50 years of use it might've been overheated, there's no
specific recent incident that i'm aware of though. for months and months
when i put the pot on the stove i could hear little "pops" of steam
explosions in between the copper and stainless, i figured something was
going on but i assumed it was a pin hole in the copper or something. i
think it happened eventually over time, and it probably wouldn't've even
come off completely except i stacked it inside another pot the same size and
when i lifted the one pot out of the other the copper stayed behind (which
startled me). maybe some long slow electrolytic reaction? once water
started getting in there, that ultra thin gap, wicked in by capillary
action, it just kept getting worse and worse? probably a combination of an
overheating incident and water getting in there? i mean, this is not an
earth shattering event but just when someone posted about laminated metal,
and "explosive welding" it reminded me of something i wanted to post
yesterday but thought was too uninteresting to bother you all with.

b.w.

"Roger Shoaf" wrote in message
...

-snip-

Here is how:
http://www.patentstorm.us/patents/41...scription.html



come to think of it, that's something i've wondered about too. even more.
how in the heck do they make aluminum stick to stainless steel, and for
thousands of heating cycles. it endures terrible abuse, fluctuations in
heat thousands of times, probably like "shock cooling" too (i have no idea
if that's an actual term)(ok, how about "quenching"?).

i tried to read that article and tried to understand it as best i can and it
still amazes me they're able to reliably get aluminum to stick to stainless
steel, and copper to stainless too (under/after thousands of heating
cycles). the article talks about bringing the two metals together under
great pressure, or putting them through a rolling mill. wow. weird. i
wouldn't think putting them through a rolling mill would make them stick,
more like probably resist to an even greater degree wanting to stick
together, like work hardening them both. and so like they make a round disc
of copper stick to a sheet of stainless, but they can accurately register
it?!

hey, i guess for that matter, aren't some u.s. coins bimetallic?

i know they can get dissimilar metals to stick together using explosive
welding, but how to they do it otherwise? that's, as far as i know, a very
rare and extremely limited technique.


b.w.

"William Wixon" wrote in
:

snip
hey, i guess for that matter, aren't some u.s. coins bimetallic?

i know they can get dissimilar metals to stick together using
explosive welding, but how to they do it otherwise? that's, as far as
i know, a very rare and extremely limited technique.

US coins used to be explosively welded. I assuem that is still what they
do. The use large thick sheets, and then roll them out thin. That way
they get a lot of welded metal per bang.

Doug White

On Mon, 9 Nov 2009 01:46:25 -0600, "William Wixon"
wrote:


come to think of it, that's something i've wondered about too. even more.
how in the heck do they make aluminum stick to stainless steel, and for
thousands of heating cycles. it endures terrible abuse, fluctuations in
heat thousands of times, probably like "shock cooling" too (i have no idea
if that's an actual term)(ok, how about "quenching"?).

i tried to read that article and tried to understand it as best i can and it
still amazes me they're able to reliably get aluminum to stick to stainless
steel, and copper to stainless too (under/after thousands of heating
cycles). the article talks about bringing the two metals together under
great pressure, or putting them through a rolling mill. wow. weird. i
wouldn't think putting them through a rolling mill would make them stick,
more like probably resist to an even greater degree wanting to stick
together, like work hardening them both. and so like they make a round disc
of copper stick to a sheet of stainless, but they can accurately register
it?!

hey, i guess for that matter, aren't some u.s. coins bimetallic?

i know they can get dissimilar metals to stick together using explosive
welding, but how to they do it otherwise? that's, as far as i know, a very
rare and extremely limited technique.


b.w.


I remember reading that the process used by the Mint for forming
tri-clad coins was invented (patented?) by the company that makes the
very good but outrageously expensive All-Clad cookware. I think that
their sucess at the coin process led them to introduce the cookware.

Joe

"Joe" wrote in message
...
On Mon, 9 Nov 2009 01:46:25 -0600, "William Wixon"
wrote:

I remember reading that the process used by the Mint for forming
tri-clad coins was invented (patented?) by the company that makes the
very good but outrageously expensive All-Clad cookware. I think that
their sucess at the coin process led them to introduce the cookware.

Joe

DuPont patented the process of explosion welding that was originally used
for the clad coins, but they stopped using the method somewhere along the
line and now use some sort of rolling method to do it.

http://www.dynamicmaterials.com/data...%20History.pdf


--
Roger Shoaf
If you are not part of the solution, you are not dissolved in the solvent.

"Roger Shoaf" wrote in message
...

"Joe" wrote in message
...
On Mon, 9 Nov 2009 01:46:25 -0600, "William Wixon"
wrote:

I remember reading that the process used by the Mint for forming
tri-clad coins was invented (patented?) by the company that makes the
very good but outrageously expensive All-Clad cookware. I think that
their sucess at the coin process led them to introduce the cookware.

Joe

DuPont patented the process of explosion welding that was originally used
for the clad coins, but they stopped using the method somewhere along the
line and now use some sort of rolling method to do it.

http://www.dynamicmaterials.com/data...%20History.pdf


--
Roger Shoaf
If you are not part of the solution, you are not dissolved in the solvent.



Kaiser Steel figured out the original Aluminum to steel "welding" Was used
in the armor plating of tanks. Abrams I think.

Bill McKee wrote:

Kaiser Steel figured out the original Aluminum to steel "welding" Was used
in the armor plating of tanks. Abrams I think.


Armco steel, (Now A-K Steel) developed the aluminum clad stainless
steel used for catalytic converters. It was great for body work, too.



--
The movie 'Deliverance' isn't a documentary!

"Michael A. Terrell" wrote in message
m...

Bill McKee wrote:

Kaiser Steel figured out the original Aluminum to steel "welding" Was
used
in the armor plating of tanks. Abrams I think.


Armco steel, (Now A-K Steel) developed the aluminum clad stainless
steel used for catalytic converters. It was great for body work, too.



--
The movie 'Deliverance' isn't a documentary!

I got to tour the Armco rolling mill in Middletown, OH when it opened. One
of the more impressive experiences. 50 ton block of steel goes into an oven
to get red hot and then sheared off in to manageable pieces. That
eventually are rolled out to very long sheets of steel. Those big rolls of
steel you see at times.

Wareever pot so it looks like - Might have been electro-spotted in a press.
Looks like some heat spots here and there and in a ring.

Martin

William Wixon wrote:
"Martin H. Eastburn" wrote in message
...
Explosive welding.
Simple as that.
Martin

N_Cook wrote:
Interesting , but no further forward. Looks as though these froststats
will
remain froststats. Surprising ping and bounce as much as six inches on
change of state, the loud ping is somewhat damped when inside the casing.
Need freezer spray to change the state of these discs (hysteresis and all
that). When back to body temp I tried grinding a spot in the centre of
the
concave side, no change in set temp. Tried 4 diametrical marks on the
concave side , no change in response. Tried deeper but small 8 cuts just
on
the perphery, now no ping but slowly migrates from one state to the other
,
still requiring freezer spray. I wonder how they "weld" these 2 materials
together.


(sorry for the digression.)
huh! yesterday i was going to ask how they make copper clad stainless steel
cookware but i thought it was too dumb and too trivial a question to ask.
couple days ago i had a copper clad stainless pan delaminate the copper
cladding and was stunned. made me wonder how they attach it in the first
place. i'm guessing some sort of furnace brazing process(?). this pan is
probably over 50 years old, i think this is one of the pans my mother got as
a wedding present in the 50's. i've seen stuff (on tv and in books) about
explosive welding but am totally assuming that's NOT how they make copper
clad cookware.

http://www.frontiernet.net/~wwixon/delamination.jpg

b.w.

Bill McKee wrote:

"Michael A. Terrell" wrote in message
m...

Bill McKee wrote:

Kaiser Steel figured out the original Aluminum to steel "welding" Was
used
in the armor plating of tanks. Abrams I think.


Armco steel, (Now A-K Steel) developed the aluminum clad stainless
steel used for catalytic converters. It was great for body work, too.



--
The movie 'Deliverance' isn't a documentary!

I got to tour the Armco rolling mill in Middletown, OH when it opened. One
of the more impressive experiences. 50 ton block of steel goes into an oven
to get red hot and then sheared off in to manageable pieces. That
eventually are rolled out to very long sheets of steel. Those big rolls of
steel you see at times.


I lived near the 'Project 600' plant for 20+ years. The original
'rolling mill' was built in the late 1800s. 'Project 600' was its
replacement and the first computerized steel mill in the US. The air
was red with rust, until the old mill was decommissioned, years after
'Project 600' was in full operation. It was used to make specialty
steels, while 'Project 600' made steel for the big three auto companies
and several companies that built major appliances. It also made the
steel skin for their 'Armco Steel Buildings' division.

Early pilots used the red cloud as a navigation aid. Some days it
could be spotted 100 miles away. The original plant had so much of that
fine rust clinging to the inside walls and roof that part of the complex
collapsed.

I had a friend who was their analytic chemist. He did all the stack
sampling tests, as well as chemical testing of the various alloys. He
got me a few pieces of aluminized stainless in the late '80s to repair
the sliding doors on my stepvan. That stuff was hard to drill!


--
The movie 'Deliverance' isn't a documentary!

"Michael A. Terrell" wrote in message
...

Bill McKee wrote:

"Michael A. Terrell" wrote in message
m...

Bill McKee wrote:

Kaiser Steel figured out the original Aluminum to steel "welding" Was
used
in the armor plating of tanks. Abrams I think.


Armco steel, (Now A-K Steel) developed the aluminum clad stainless
steel used for catalytic converters. It was great for body work, too.



--
The movie 'Deliverance' isn't a documentary!

I got to tour the Armco rolling mill in Middletown, OH when it opened.
One
of the more impressive experiences. 50 ton block of steel goes into an
oven
to get red hot and then sheared off in to manageable pieces. That
eventually are rolled out to very long sheets of steel. Those big rolls
of
steel you see at times.


I lived near the 'Project 600' plant for 20+ years. The original
'rolling mill' was built in the late 1800s. 'Project 600' was its
replacement and the first computerized steel mill in the US. The air
was red with rust, until the old mill was decommissioned, years after
'Project 600' was in full operation. It was used to make specialty
steels, while 'Project 600' made steel for the big three auto companies
and several companies that built major appliances. It also made the
steel skin for their 'Armco Steel Buildings' division.

Early pilots used the red cloud as a navigation aid. Some days it
could be spotted 100 miles away. The original plant had so much of that
fine rust clinging to the inside walls and roof that part of the complex
collapsed.

I had a friend who was their analytic chemist. He did all the stack
sampling tests, as well as chemical testing of the various alloys. He
got me a few pieces of aluminized stainless in the late '80s to repair
the sliding doors on my stepvan. That stuff was hard to drill!


--
The movie 'Deliverance' isn't a documentary!


I remember seeing a red cloud above some buildings. Was 1968 and I worked
for NCR in those days and wife and I went down to tour the plant when they
opened it to the public for the grand opening. Was in Dayton for a class.
Growing up 10 blocks from San Francisco bay, did not see a lot of rolling
mills here.