Sciencemadness Discussion Board

Curie Temperature of Monel

Morgan - 9-6-2014 at 17:59

So I had watched this video and realized I had something made of monel in the garage.
PH EM MI DEMO 70025A V0207 Curie Point Demonstration with Monel Metal
https://www.youtube.com/watch?v=7KcSM-ossxo

But in my case the monel didn't have enough strength to stick to the neodymium magnet at room temperature or even after being in the freezer a few minutes however a longer stay until frosty cold improved things.
I'm not sure if I heated the part and let it cool slowly to anneal it perhaps or if setting it on some dry ice for a time would make the attraction stronger still. Monel 400 has a Curie temperature of 20 -50 C.
http://www.espimetals.com/index.php/technical-data/156-monel...

Tidbits
"It will be noted in Table 2 that the Curie
temperature lies within the ambient range. It is affected
by variations in chemical composition. The values
shown represent the range which can be expected from
normal production; therefore, some heats will be
magnetic at room temperature and others not. If there is
a strong requirement for nonmagnetic characteristics,
other MONEL alloys should be considered."
http://www.specialmetals.com/documents/Monel%20alloy%20400.p...

I came across some platinum alloys that had a very low Curie temperature. Funny what 1.5% cobalt does to Pt.
There's a chart here page 1657 with quite a range of possible temps.
http://authors.library.caltech.edu/2595/1/CONpr30b.pdf

Thermoelektrischer Motor,Thermoelectric Engine
https://www.youtube.com/watch?v=KHtrTVmRsC8

Curie Effect Magnetic Heat Engine
https://www.youtube.com/watch?v=RWrTvB-oK94

Things that are made of monel
WWII dog tags, old golf clubs, valves in musical instruments,
monel fishing leader, non-rust staples for staple guns, monel guitar strings, reading glasses rims, belt buckles, non-rust bolts marine applications, aircraft safety wire, HF handling, etc.

Another thing I was thinking of would be to make a monel fluid similar to ferrofluid for a demonstration or odd toy of some sort.
Any thoughts on annealing or other characteristics or properties welcome.

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IrC - 9-6-2014 at 18:35

Could the difference in properties you are seeing be related to the alloy you have? 63 percent Ni is all you can typically count on, the amounts and choice of other elements varies greatly. Maybe for a particular property they desired a non typical choice of other components is having a greater than usual affect on the Curie point? Possibly you have Monel K-500 instead of say 400?


Morgan - 9-6-2014 at 19:02

Yes, I figured the ratio of nickel to copper might be the culprit. I fiddled with a 1000 pack of 9/16 inch monel staples today at a hardware store. They too didn't have much attraction to the magnet I took with me. But the temperature probably wasn't below 70 F, the cutoff point for the 400 series.

Here's something else kind of interesting when I started dinking around with this topic. I was toying with one of the pieces of inconel tubing I got from a metal scrapyard and noticed it wasn't at all attracted to a magnet. The tubing was used in a heat exchanger perhaps, with a seamless mirror finish if you look down the inside of it. I dropped a neodymium magnet down it's length and nothing. But then I wondered if cooling it might make it so after watching a gandolinium demo of the rare earth being attracted to a magnet after a dipping in cold water.
Gadolinium - Science experiment
https://www.youtube.com/watch?v=mrthB0n-Yd4

And lo there is a case where inconel 718 becomes strongly magnetic according to this NASA incident, a malfunction.
"Near liquid hydrogen temperatures, Inconel 718 used in the armature of the LVDT became strongly magnetic."
http://link.springer.com/chapter/10.1007%2F978-1-4613-9880-6...

In college I recall my astronomy professor passing around meteorites and some were nickel-ferrous. It might be fun to make a Curie motor out of one, something different.

See how low the thermal conductivity of monel is.
http://www.engineeringtoolbox.com/thermal-conductivity-metal...

A couple more frost/no frost photos



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[Edited on 10-6-2014 by Morgan]

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Morgan - 11-6-2014 at 12:01

I saw this item in a Habitat for Humanity store, a place to buy used materials and on the shelf was this inconspicuous little beat up bag. It might make a cute little Curie motor if suspended from a wire. It's strongly attracted to a magnet and weighs 12.44 grams.
I'm trying to balance two things - finding the lowest Curie point alloy with the strongest attraction to a magnet in a room temperature setting or thereabouts. The monel I tested has a low Curie temperature but not a very strong attraction like pure nickel or iron. Also it would be nice to find something having a narrow window where the Curie temperature transitions quickly for the on/off effect.
Here's the humble find today for one dollar and a gold plated coffee filter I thought about trying out for a Curie motor too. I don't know what the base metal is underneath the gold plating, but it may heat and cool quickly being thin and having a perforated surface area.

http://books.google.com/books?id=pGnwhznZNF0C&pg=PA148&a...

http://www.meteorcrater.com/

Funny to read there are only two extreme choices if you want to buy a sample. The next size up from the authentic crater dust is a bit more. ha
http://www.meteorcrater.com/Online-Store



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Morgan - 12-6-2014 at 12:12

I cut the coffee filter apart and retrieved two remarkably heavy sheets of gold plated metal. My initial search yielded no results when I tried to find out what it was made of but today I decided to just type gold plated nickel coffee filter in Google on a hunch and came up with this proof. You can't really read it upside down but the filter has the same words Swiss Gold on one side opposite the word Braun.
Oddly the two mesh sheets together weigh the same amount as my little meteorite.

"The merchandise is a reusable replacement filter for paper coffee filters. It is used inside the brewing basket
of an automatic drip coffee maker. It is made of gold-plated nickel mesh in a frame of plastic."
"The applicable subheading for the Swiss Gold Coffee Filter will be 8516.90.6000, Harmonized Tariff Schedule of the United States (HTS), which provides for parts [of coffee or tea makers]. The rate of duty will be 3.9 percent ad valorem."
http://rulings.cbp.gov/detail.asp?ru=876339&ac=pr

Another interesting nickel alloy is Invar. I searched the search engine but only came up with a multitude of hits on the word invariably or invariable and gave up. Funny that that's where the alloy got it's name. I thought there would be something about it here because it's used with glass for the low expansion rate and other qualities.
I saw a 30 pound roll of invar wire on ebay for $400.00 and several watches made of it.

"It was invented in 1896 by Swiss scientist Charles Édouard Guillaume. He received the Nobel Prize in Physics in 1920 for this discovery, which enabled improvements in scientific instruments."
http://en.wikipedia.org/wiki/Invar

[Edited on 12-6-2014 by Morgan]

IrC - 13-6-2014 at 14:42

http://www.drkfs.net/SUSCEPTIBILITYOFMONEL.htm

Have you looked at this site? A post about vacuum in another thread linked to another page on this site. Searching the site, I found an amazing wealth of very useful home-built scientific equipment projects.

http://www.drkfs.net/index.htm

An Experimental Curie Point Heat Engine

http://www.drkfs.net/HEATENGINE.htm

I think I will be spending some time on the site there are so many great projects.

http://www.drkfs.net/SIMPLEGAUSSMETER.htm

http://www.drkfs.net/CALIBRATINGGAUSSMETER.htm

http://www.drkfs.net/FIELDATPOLEOFMAGNET.htm

So many more pages to study. The place is a madsci goldmine of information.

Morgan - 13-6-2014 at 15:19

Thanks for the links. That was an interesting monel 400 engine and seems to agree with my freezer chilled monel experiment. The monel fittings I found in the garage didn't seem to have nearly the attraction as pure nickel. My nickel screen is quite strong but requires higher heat, around 350 C. There are a few alloys of monel so mine may not have been the best.

I have sort of a weird question. I was thinking about driving a tiny Curie engine with a flameless heat source using either some platinum gauze, platinized wick, a platinum ceramic room fragrance burner that's made to run on isopropyl alcohol, or palladium on carbon or silica that I have. But then just before falling asleep I recalled the nickel carbonyl reaction where nickel reacts with carbon monoxide. And I came across some mention on this site that the nickel has to be reduced with hydrogen and in the absence of air for the surface to be reactive.
But when you impregnate the palladium pellets or other catalysts with methanol, they heat up spontaneously and not all of it turns into CO2 and H2O. You can smell formaldehyde which I read is a reducing agent.
Is there any possibility the products of the incomplete combustion of methanol might react with a heated nickel screen making any trace of nickel carbonyl? I thought it would be a nice variation on a theme, switching off the magnetic attraction of the nickel screen with a PGM but I don't want to win a Darwin award in the process. The nickel screen would pass over the platinum gauze heating element.

Here's some of the catalysts again for review. The petri dishes will get very hot if you mist them with methanol and the dull powdery one of platinum on alumina ignites.
http://www.sciencemadness.org/talk/viewthread.php?tid=15370&...

Here's a somewhat artistic slant on the Curie motor that caught my eye. There's a lot of creative devices you could make using the Curie point effect.
Decorative Thermomotor #1
https://www.youtube.com/watch?v=kRSMbkbU_kE

This one is the fastest I've seen so far, but it seems like you could design one a little faster with some fine tuning and creativity.
Curie motor videó
https://www.youtube.com/watch?v=LexcwNDW-2s

[Edited on 14-6-2014 by Morgan]

IrC - 13-6-2014 at 16:54

You need someone like woelen to answer this but I do know I would avoid nickel carbonyl at all costs. Unless one is trying for the Darwin award. I spent the last while looking through that site and I wish there were more projects, also at least 3 pages have missing images which is annoying. At least the pages relating to this thread (monel, magnetics, etc.) are complete. I see 3 or 4 items I am going to build from the info. I like his vacuum gauge:

http://www.drkfs.net/pirani.htm

Also the solid state mini cooler looks very useful:

http://www.drkfs.net/CRYOSTAT.htm

I hope he is going to be adding more instrument projects.

A thought: I remember in my youth using those palm (or pocket) warmers which used regular old fashioned lighter fluid. Might do some searching to study the process/construction. No doubt a catalyzed slow combustion. Could you not obtain one of them and hardware hack it for the materials to build a very safe heater for your engine? Besides lighter fluid is still easy to obtain everywhere and low cost. Seems like a better idea that using highly toxic materials.

From http://en.wikipedia.org/wiki/Hand_warmer

"Lighter fuel hand-warmers use lighter fluid (petroleum naptha) which reacts with a platinum catalyst to release heat by oxidation reactions. These can be re-used by simply refueling"

No doubt you could find one of these and take it apart for the materials to build your needed heat source at low cost. A bonus is as I said safe, and cheap to refill.

http://www.ebay.com/itm/New-Platinum-Handwarmer-Portable-Poc...

Ten bucks and free shipping. Take this apart for the needed materials.

Morgan - 13-6-2014 at 18:10

Essentially, this is the heating element out of a hand warmer. It had a spring inside it to hold its shape and perhaps to act as a heat reservoir. I just stuck it on a metal handle to hold it and took out the inner spring.
It's funny with naphtha following the instructions you have to light it and let it burn for a bit before blowing it out to get it started/to sustain, but filled with methanol in the tank it heats up spontaneously and it gets so hot you can't hold the hand warmer.
https://www.youtube.com/watch?v=UtkEfzpZ4Sg

This is the platinum on alumina powder 1%.
https://www.youtube.com/watch?v=gJuT5QtU54Q
https://www.youtube.com/watch?v=h3lS3TBuntw

Also a Tesla tidbit.
Tesla’s Thermomagnetic Motor
http://www.teslauniverse.com/nikola-tesla-article-teslas-the...

This is a piece of platinum gauze I had reacting with 91% isopropyl alcohol. One time I had a small jar with methanol and some coiled platinum wire mounted to the lid with a few holes for air. I left it cycling and the next morning it was still whooshing/chuffing ever so weakly every minute or so when the vapor inside the jar refreshed and ignited from the glowing Pt wire. The methanol had become watery and weaker however.
http://www.pulse-jets.com/phpbb3/download/file.php?id=13771&...

I bought one of these from a thrift store, it was made to run on isopropyl but methanol would work too, or hydrogen or a few others I suppose. It has a cylindrical ceramic material for the heating element, like a large pellet sort of.
http://en.wikipedia.org/wiki/Fragrance_lamp
http://iscentu.files.wordpress.com/2014/03/img_lamp2.jpg

[Edited on 14-6-2014 by Morgan]

Morgan - 18-6-2014 at 10:43

If you were working with nickel or monel screen, gauze or maybe even in sheet form, if heating it with a heat source that had incomplete combustion, perhaps there would be a risk to watch out for. This page is kind of scant but concerning.
Or maybe something other than CO could react with the metal surfaces and stairstep to yield CO for a nickel carbonyl reaction to take place. As I don't know, I wouldn't want to risk my health without some certainty of what's possible.

Occurrence and Analysis of Organometallic Compounds in the Environment
http://books.google.com/books?id=WVbGAzQ8pg4C&pg=PA208&a...

Morgan - 15-7-2014 at 16:52

Well I finally got around to trying a little colder temperatures than my freezer. It really did improve the strength by quite a bit. I just wonder if it would get stronger still with liquid nitrogen or have I maxed out?

Curie Temperature Investigation of a Monel Alloy
https://www.youtube.com/watch?v=5meS1MBszQw

Morgan - 3-8-2014 at 15:31

"The description of this discovery by Ludwig Mond's son, Alfred, is a compelling case for observing closely every aspect of your experiment."
"It has taken human lives, and given birth to an industrial process."
http://www.rsc.org/chemistryworld/podcast/CIIEcompounds/tran...

Morgan - 12-8-2014 at 06:34

Here seems to be a reverse way to bring about the Curie point "alignment" by heating instead of cooling.

New Alloy Can Convert Heat Directly Into Electricity (US)
http://www.france-metallurgie.com/index.php/2011/06/29/new-a...

"In the lab, University of Minnesota researchers show how a new multiferroic material they created begins as a non-magnetic material then suddenly becomes strongly magnetic as the piece of copper below is heated a small amount. When this happens, it jumps over to a permanent magnet. This demonstration represents the direct conversion of heat to kinetic energy."

https://www.youtube.com/watch?v=pWCz2lP7WcU

Viewer comment
"I liked the part where the metal flake moved." ha

A more telling perspective of the design
http://wattsupwiththat.files.wordpress.com/2011/06/nfig002.j...
http://wattsupwiththat.com/2011/06/22/new-multiferroic-alloy...

[Edited on 13-8-2014 by Morgan]

Morgan - 12-9-2014 at 07:04

This seemed a good candidate or demonstration to illustrate how "changing the temperature" changes the Curie point. The other day I heated some monel screws (roughly 2/3 nickel, 1/3 copper) and then let them cool to room temperature. They became more ferromagnetic than the non-heated ones. But here using a nickel-iron Invar type alloy, they were able to use dry ice to bring about/trigger a significant change in its properties. Before reading this article or book, I had entertained the thought that cooling might also alter the attraction to a magnet in the same way heating the monel did, but not to the extent or degree in the passage below.
Maybe thermal imaging would capture something akin to the recalescence seen when heating and cooling some red-hot iron alloys, if there's some sort of shift as the cold sample warms to room temperature?

"Later in the same year Hopkinson discovered that a sample of 25% nickel steel furnished to him was practically non-magnetizable at ordinary temperatures ... it retained its non-magnetic condition while being heated up to 700 or 800 C and did not recalesce on cooling from a high temperature. But when the temperature was reduced to a little below 0 C, ferromagnetic properties appeared, which were strongly intensified by further cooling. Moreover, cooling to -50 C with solid carbon dioxide effected such a transformation that, when the specimen was returned to 13 C, it was found changed from a non-magnetizable to a decidedly magnetizable substance; and it remained magnetizable on heating until 580 C was reached. In the neighborhood of this temperature it again became magnetizable and continued so on cooling to the temperature of the room. By these experiments Hopkinson showed that the material can, at ordinary temperatures, exist in either of two quite different states. both of which are stable." (page 4)

Invar and related nickel steels April 4, 1916
http://books.google.com/books?id=ztAOd_hH7h4C&pg=PA23&am...

Recalesence
https://www.youtube.com/watch?v=33neAGXxZ94

ESL @ ISU - 50-50 Co-Pd recalescence
"50% Cobalt 50% Palladium alloy showing undercooling and recalescence phenomena at Iowa State University."
https://www.youtube.com/watch?v=aUt2iYGNnlU

[Edited on 12-9-2014 by Morgan]

Morgan - 24-10-2014 at 19:58

I thought this was an interesting property, something you might test with an ordinary U.S. nickel being an alloy of 25% nickel and 75% copper. I was hanging a nickel by a piece of thread and taped the thread to a shelf and noticed the nickel lined up with an N52 magnet when placed near, presenting an edge to the magnet. I was able to start it swaying more and more by coaxing it in phase with the motioin of the nickel. Maybe a stronger response could be seen if heated or if you designed it somehow to be more sensitive or in a way to amplify the response. It would be just the opposite of a typical Curie point demonstration where the object releases when heated, hopefully illustrative enough to show a lean towards the magnet if possible when heated and suspended from a thin wire or some such design. Of course paramagnetic forces aren't much to work with and this could be challenging.

"For amounts of nickel from one percent up to 30 percent the alloy, while paramagnetic in most respects, does not obey any known law of paramagnetism with regard to temperature. As the temperature is increased the susceptibility first increases and then decreases, the maximum occurring in the neighborhood of the Curie point for nickel." (Nickel has a Curie point of 354° C)
Magnetic Properties of Copper-Nickel Alloys
http://journals.aps.org/pr/abstract/10.1103/PhysRev.38.828


[Edited on 25-10-2014 by Morgan]