Could somebody give me evidence that friction causes molten metal?

[Anti-sophist]

http://web.mit.edu/course/other/machineshop/Grinder/aluminum.con.html

Please note the melted aluminum on this grinding wheel. Grinding is friction.

There are some materials that can cause major problems if you try to grind them. In particular, the big no-no with grinders is aluminum. Aluminum melts easily, and if you were to try to grind down aluminum, it would start to melt and the aluminum would coat the wheel.

 

[delphi_ote]

gravy my source is www.debunking911.com which claims it was friction. also another thread in this forum claims it

The word "friction" does not appear anywhere on that page. If you're referencing a particular article, find it and link directly to it. Maybe even quote it. When you make a claim, it is not someone else's job to hunt down just what it is you are talking about.

If you fail to point people directly to what it is you are claiming the source said, they will suspect you are misrepresenting the source.

At the moment of the initiation of the pressure pulse due to floors stripping off, the initial forces will all be on just the outside edges of the most exterior of the box columns in the core. But as the calculation shows, the pressure required is less than 1/40th of the yield strength. So the box columns would not show signs of yielding, even with highly asymmetric patterns of the initial forces.

http://www.debunking911.com/moltensteel.htm

The only likely source of the heat great enough to actually "melt" significant quantities of iron in the piles (or even just raise so much of it to red-hot or to 2000F) would be chemical energy (i.e., "combustion" of some sort).

http://www.debunking911.com/ironburns.htm

In this case, it looks like people would be right to suspect you were misrepresenting the source.

 

[pdoherty76]

http://web.mit.edu/course/other/machineshop/Grinder/aluminum.con.html

http://web.mit.edu/course/other/machineshop/Images/gr_al.jpg


Please note the melted aluminum on this grinding wheel. Grinding is friction.

very helpful. now tell me what this has to do with steel

 

[pdoherty76]

are you looking for a reference to a paper that states that molten metal at the WTC site was caused by friction?

I do not believe that NIST addressed the "molten metal" at the site, and I am not sure, to them, what the relevence would be in doing so. The importance of this, is only in the minds of CTers...noone else.

TAM

Pools of molten metal are not characteristic of things falling.

I would love to see u produce an example of a builing collapse before or since 911 that has had molten metal involved

 

[Gravy]

Yes, anti-Sophist, please provide a photograph of steel being ground. AHA! Caught you!

 

[Gravy]

Pools of molten metal are not characteristic of things falling.

I would love to see u produce an example of a builing collapse before or since 911 that has had molten metal involved

Please reference similar building collapses so we can look into it.

 

[Zep]

very helpful. now tell me what this has to do with steel

Please tell us where steel was the metal claimed to be molten in the WTC collapse.

 

[defaultdotxbe]

very helpful. now tell me what this has to do with steel

anyone else see that goalpost move?

the topic was about molten metal, now we are talking about steel

 

[eeyore1954]

So TAM you are claiming some steel falling from a thousand feet is comparable to shuttle re-entry? Game of jenga anyone?

I haven't heard of any scientists claiming the supposed molten steel found in the rubble was caused by friction alone. You don't think there was a lot of material that got buried in the collapse that was burning and/or extremely hot.

Do you think there wasn't any additional heat generated by the collapse. You do believe that friction can cause heat don't you. A little mental experiment would be If you dragged a piece of steel behind a car at 60 mph for a quarter of a mile what do you think would happen to the temperature of the steel. This isn;t my field of expertise but I wouldn't think picking it up with your bare hand would be a good idea.

BTW
When the Space Shuttle reenters Earth's atmosphere,
the friction of the air can get the temperature up as high as 3000 F
Shuttle reentry is a controlled, unpowered glide that starts at 18,000
miles per hour, and touches down at about 220 mph. They start entering
the atmosphere at a 40 degree angle of attack. If it's any steeper, the
shuttle will burn up (even with the nifty tiles), and if it's any
shallower, the shuttle will skip off the atmosphere like a stone over
water. Interesting stuff!
according to http://www.madsci.org/posts/archives/apr2001/987003987.Eg.r.html

 

[Pardalis]

anyone else see that goalpost move?

You did. You're alert.

 

[Zep]

More:

...none of these stories prove there was molten (as in liquid) steel at the WTC. There's no evidence temperatures were hot enough to produce that (whatever the energy source), and some of the stories claiming "molten steel" have built-in implausibilities. There was certainly glowing metal, but this only indicates temperatures within the range of a fire.

http://www.911myths.com/html/wtc_molten_steel.html

 

[Zep]

anyone else see that goalpost move?

the topic was about molten metal, now we are talking about steel

Hence my question!

 

[defaultdotxbe]

I haven't heard of any scientists claiming the supposed molten steel found in the rubble was caused by friction alone. You don't think there was a lot of material that got buried in the collapse that was burning and/or extremely hot.

Do you think there wasn't any additional heat generated by the collapse. You do believe that friction can cause heat don't you. A little mental experiment would be If you dragged a piece of steel behind a car at 60 mph for a quarter of a mile what do you think would happen to the temperature of the steel. This isn;t my field of expertise but I wouldn't think picking it up with your bare hand would be a good idea.http://www.madsci.org/posts/archives/apr2001/987003987.Eg.r.html

not only that, but bending metal would also produce heat

 

[Anti-sophist]

very helpful. now tell me what this has to do with steel

Right after you tell me what molten steel has to do with 9/11.

 

[pdoherty76]

ok thanks people. i have been informed

 

[Mr. Scott]

Melting Steel Girders and Bending Spoons with Friction

I once asked if bending metal, like bending a spoon, caused enough heat to melt it. I was assured that, yes, what happened when you bent a spoon is that microscopic areas of the metal briefly reach melting point. Immediately thereafter, the melted spots spread their heat to the surrounding metal and re-solidify, leaving tiny defects in the spoon's structure. Bending the spoon fast enough by hand can cause enough heat buildup to not just make the metal warm -- even warm enough to burn you. The accumulation of re-melted spots will also materially weaken the spoon enough to make it soft and fall apart.

Someone correct me if I'm wrong.

There has to be, though, a ceasing of friction once the metal reaches liquid state, so the metal, I would think, would only reach melting point then would hit a temperature "brick wall" and not get any hotter because there's too little friction in liquid metal. The heat would be distributed and dissipated into the surrounding material.

In the case of a building like the WTC there is a mix of steel, lots of aluminum, concrete, and asbestos -- all with different coefficients of friction and melting and burning temperatures. Rub them all together really fast and I can believe the lower temperature stuff would melt from the friction.

 

[Popeholden]

doherty, what makes you think the molten metal found at the WTC was steel? did anyone do any tests on it?

 

[Anti-sophist]

There has to be, though, a ceasing of friction once the metal reaches liquid state, so the metal, I would think, would only reach melting point then would hit a temperature "brick wall" and not get any hotter because there's too little friction in liquid metal. The heat would be distributed and dissipated into the surrounding material.

In the case of a building like the WTC there is a mix of steel, lots of aluminum, concrete, and asbestos -- all with different coefficients of friction and melting and burning temperatures. Rub them all together really fast and I can believe the lower temperature stuff would melt from the friction.

You also need to consider what changing pressure would do to molten materials. You'd have an "interface" of melted stuff between two grinding materials. This is a non-trivial problem to analzye much beyond the point of proof-of-concept. Anyone who claims that friction (both external in the form of sliding and "internal" in things like deformation) can't melt metal just doesn't understand the very basics of the first law of thermodynamics.

 

[TjW]

Also, anyone who was interested in whether friction could make metals hot enough to melt could Google or Wiki "friction welding" "stir welding"

 

[Christophera]

so in short none of you can give me a link to an academic paper that shows this phenomenon exists? yep those debunking sites are very scientific

Good thread, good point, good post.