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A Foundry in Every Kitchen
WolfWithoutAClause writes "Bored with making the same old food or
plasma in your microwave? David Reid sounds like he is. He's using his domestic microwave oven to melt iron, silver and bronze! Over 900C! I don't know about you, but I'm going to be checking the temperature of my pizza rather more carefully in future..."
Try putting in a CD (Yet another use for those AOL 7.0 discs that they keep sending)
:-)
A burned out light-bulb causes some interesting things to happen as well
Jesus used to be my co-pilot, but we crashed in the mountains and I had to eat him.
This is sweet! I could forge my own One True Ring - Deep inside Mount Panasonic, a master ring was made on High-Power to rule them all!
I don't know about you, but I'm going to be checking the temperature of my pizza rather more carefully in future...
Who in the world microwaves pizza? It gets very soggy and loses almost any redeeming qualities.
Try actually reading the article. One: they've already done it. Two: it's not the entire inside area of the microwave that's reaching those tempuratures, just the area inside several layers of material that convert microwaves to heat, plus the interior surfaces of the microwave have been layered with insulation to protect them.
microwaves are high voltage, high current devices. they can kill you EVEN IF THE POWER IS OFF AND THE DEVICE IS UNPLUGGED (ex: by discharging of a large capacitor). Unless you really know what you are doing, don't open one up. i've been trained in servicing electronics, and even i wouln't go near one of these things.
see: Notes on the Troubleshooting and Repair of Microwave Ovens for more information.
There's nothing wrong with heating up a metal in a microwave, that in itself will not ruin the unit. What is a big problem is the heated item melting the inside floor of the oven due to (drum roll, please), HEAT! The item gets hot, and melts a big hole in the floor, therefore ruining it. So go ahead and heat metals in your microwave, just don't let it touch the insides directly. That means using a plate, cover, etc.
Back in 1981, I built a small clothes dryer from a microwave. I drilled a hole in the front glass, placed a vacumm tube through it, with a vacumm pump on one side, and a vacumm flask in the m-wave. I them tested various fabrics with differing amounts of H20 in them. Amazing that a jean leg dryed in 15 minutes, tee-shirt in 5, a wool sleve in 25 minutes (low heat to avoid shrinkage). Based on energy calculations, it used about 2/3 the power and was running at lower overall temperatues (I suspected that local temps ran over boiling, but then again they do in a dryer).
I wish I had the money back then to persue the idea.
... if the microwave ran cooler (pun intended).
If the microwave could somehow have a thermostatic control, I could take a bag of grade-5 bolts and nuke them to a grade-8 tensile strength. The button for 1040-steel alloy can go next to the popcorn button.
:-)
To properly control the grain structure of the metal, the heating & cooling processes have to be controlled precisely for temperature vs. time (very non-linear and not instinctive). Introduce a quenching process in the microwave, and I bet you could make some serious bucks selling/operating this thing.
Notice how the crucible and insulating assembly looks over exposed in the photos linked from the article. I wonder if this is because they are emitting a large amount of IR? This would be invisible to the eye, but visible to a CCD camera, even through a the cheap plastic filters they use.
That's what the microwave at work is for!
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
now on slightly related topic
When food, (containing water, a very efficient absorber), is placed in a microwave field having a frequency of 2.4 5GHz, virtually all the microwave energy is converted to heat.
Now this raises all sorts of interesting safety questions about wireless networking, as well as the current generation of wireless telephones I see down at Staples, etc.
"It is a greater offense to steal men's labor, than their clothes"
Other than that, the technique sounds unnecessarily laborious and complex. There are easier ways to melt metal, even at home. Thermite, for example, should appeal to people who like fireworks. Basic textbooks on inorganic chemistry, mineralogy, and metallurgy can tell you how. (Don't people learn this stuff in high school chemistry anymore?)
Been there, done that.
Thankfully it was only somewhat superheated, leading to violent bubbling and some spill over, and not the kind of violent explosion your link suggests is possible.
Maybe the pizza isn't a very efficient absorber of energy, but the cheese certainly is.
As anyone who's ever bitten into fried mozzarella sticks can attest.. cheese is the one magic food that has the potential to turn into molten lava.
Another fun thing to do is to prove to stupid people how radiation really does cause things to become huge. Put a few large marshmallows in the microwave, and microwave them on high for 2 minutes. The marshmallows balloon up to at least 4 times the size.
A serious problem with pouring molten metals is the risk of moisture in the moulds. For example, if a fly happened to be in the mould when the metal was poured, the metal would explode from the moisture with enough force to hit the ceiling. I sure don't want to be in a room when its raining molten metal!
When i used to work as a repair tech for a local clone computer shop, i used to go and grab all the aol disks outta the modem boxes, and nuke em in the back room nuker (5 secs does it nicely), then tack em up on the shop wall. When customers would ask what the hell had happened to the cd's, i said it contained a vicous trojan horse that destroyed your tcp/ip stack (this was back when aol software had a hugely nasty habbit of utterly corrupting your ip stack) and that i was sterilizing the cd so that people didnt accidently destroy their OS. Customers would nod agreeingly afterwards.
Lawyers, MBA's, RIAA? A jedi fears not these things!
I've no quarrel with frozen pizza designed to be microwaved. When hunting and gathering one must accept what one finds. But you savages who defile perfectly excellent cold left over pizza have no place in a civilized society. Some social ills make me wonder what horrible childhood pain would cause a person to behave in such a disturbed manner. But those dysfunctional individuals microwaving delectible left over pizza, clearly they must be shot, incinerated, with their ashes encased in glass rods, buried under a mountain or maybe a salt flat, then covered with lye and never spoken of again.
When people ask "What's this world coming to?" you can be sure that people who microwave perfect precious left over pizza are at fault. Filthy animals!
--Jimmy has fancy plans; and pants to match.
Using an industrial microwave (5kW) with Nitrogen piped through a bed of Al powder I got a max of 1470 C before solid Aluminium Nitrate was formed. Temp possibly got up to 1600 C but thermocouple melted. arse. Seemed that key to getting ignition (or melting) was retaining heat. got one reaction at approx 1KW after 15 mins using carbon powder packed between 2 tubes |c| al |c| |c| al |c| Have u tried Au/Ag powders (heat much faster than solids - sorry if already posted)
Microwaves in a microwave oven are using a frequency that matches the vibration frequency of the O-H bond in water. Now if a microwave should be converted into heat, it must hit a molecule, where it can leave the correct energy. This is quantum mechanics, so only the precise amount of energy can be transferred to the vibration. If the wavelength of the microwave doesn't match, energy will not be transferred.
Now the described experiment used several different containers for the metal. These containers absorb the microwave and convert them into heat. To obtain the best container material, you should look for materials whose vibration energy of some of its atom bonding matches that of the O-H bonding in water.
The O-H bond has been chosen as most food contains water. Materials without water will not heat in a microwave oven. (Unless it contains molecules that match the frequency in other ways).
-:) Oh no - not again.
www.rednebula.com
Oh, you're all geeks.... the lot of you... Not nerds like the site says, GEEKS!
The worst thing about this is that some of you here will actually think this will Get you chicks!
Argh! I need my pills? Where are my pills?
/^[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,4}$/i
Water evaporates at lower temperature as the atmospheric pressure reduces. You wanna conserve loads of energy? Pump the air out of the dryer and apply a little heat.
Oh shit, patent, patent...
Government of the people, by corporate executives, for corporate profits.