Tuesday, February 10, 2009

Not ordinary fires

I do not want to say much about the Australian fires - but this photo of molten metal from burnt cars gives you some idea of their intensity.




For the record - apparently these were aluminium alloy wheels.  The melting point is just under 1000 kelvin.   Way hotter than lead (600 kelvin).  Iron melting point is 1800 kelvin - furnace temperature.  There are incidents of iron being serious impaired (eg children swing sets that collapsed with heat damage) but I have not seen plausible photos of iron melting like this...

J
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8 comments:

  1. AnonymousFebruary 10, 2009 at 12:01 PM

    US wildfires regularly melt traffic signs and road delimiters. In this case, could it just have been the battery? Lead has a fairly low melting point. A friends car burned out after an accident and his SCUBA weight belt made of lead completely disappeared in the trunk. (Not to put down the magnitude of the Australian fires. A lot of the remainders will probably be toxic. Not sure what happens with the sulfuric acid etc.)

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  2. John HemptonFebruary 10, 2009 at 12:13 PM

    I have heard reports of engine blocks melting. But I have not seen pictures.

    Steel clearly melted in some places.

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  3. AnonymousFebruary 10, 2009 at 10:45 PM

    I am very skeptical of that picture.

    Steel does not melt well. Iron might. Lead does. There is a lot of steel in that picture that didn't melt.

    The "flows" seem to be coming from the "axle assembly", there could have been a cast iron housing on it.

    Shame about the fires.

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  4. John HemptonFebruary 10, 2009 at 10:50 PM

    Later comments on that photo describe the metal as the alloy wheels of the car.

    What is the alloy? I have no idea...

    But the things that are iron based that melted are things like childhood swings.

    It seems that zinc coated metal didn't seem to melt. And lots of steel didn't.

    ---

    Whatever - I know some of these towns. Or knew them. They no longer exist.

    J

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  5. AnonymousFebruary 11, 2009 at 12:07 AM

    All things move toward their end.

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  6. AnonymousFebruary 11, 2009 at 7:30 AM

    that looks like aluminum, which also has a low melting point. aluminum is used in engine blocks, pistons, heads, trannie cases, wheels, radiators, etc.

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  7. AnonymousFebruary 11, 2009 at 7:33 AM

    Picture #23

    http://www.boston.com/bigpicture/2009/02/bushfires_in_victoria_australi.html


    I've had a car burned once and the aluminium cilinderhead was melted and the chassis buckled and some of these places look like a blast furnace.

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  8. John HemptonFebruary 11, 2009 at 7:53 AM

    It was aluminium - which has a medium melt point - just shy of 1000K.

    I have seen a few photos now of engine blocks (or at least the aluminium heads) melting.

    J

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