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Re: Golka video: Ball Lightning in lab. WHAT?!!!!!



Original poster: "Mike" <induction@xxxxxxxxxxx>

Hi Mark,
Just FYI, the lower electrode, that one near the water with all the discharge chunks taken out, this is aluminum. At one point in the fairly long experiment series, he had the swinging vertical bar as aluminum also but at some point replaced that one with steel. In this video, I can not say if the vertical electrode is iron or aluminum but he is certain that the lower one was always aluminum.
Something to keep in mind here that may be of value. Of course we have all seen red hot steel because of it's melting temperature but I have never seen red hot aluminum, solid or liquid. It also has some interesting properties, please see below link. Remember as you read below that we are looking at AL, maybe with steel, onto or into water. Even given the vapor barrier note AL has affinity for hydrogen and molten will suck it up. The Oxygen content is fairly high in air, hydrogen much smaller ratio. Question, does very high temperature product placed into water break the bond of H2O? Would the AL get enough from air or is the water adding to the Hydrogen? Something else, once the molten aluminum takes in the hydrogen, as it goes from molten to solid it now can not hold it, producing perhaps the gas pockets I've seen in the hollow shells with slag bonding to a metal core, is this now freed hydrogen adding to the combustion and light output? I do wonder.
http://www.key-to-metals.com/Article12.htm where you can see some points such as that: (Quote)
Hydrogen Solubility. Hydrogen dissolves very rapidly in molten aluminum. However, hydrogen has almost no solubility in solid aluminum and it has been determined to be the primary cause of porosity in aluminum welds. High temperatures of the weld pool allow a large amount of hydrogen to be absorbed, and as the pool solidifies, the solubility of hydrogen is greatly reduced. Hydrogen that exceeds the effective solubility limit forms gas porosity, if it does not escape from the solidifying weld. (Un-Quote) (Quote) Oxide. Aluminum oxide melts at about 2050 oC which is much higher than the melting point of the base alloy. If the oxide is not removed or displaced, the result is incomplete fusion. In some joining processes, chlorides and fluorides are used in order to remove the oxide contain. Chlorides and fluorides must be removed after the joining operation to avoid a possible corrosion problem in service. (Un-Quote) (Quote) Thermal Characteristics. The thermal conductivity of aluminum is about 6 times that of steel. Although the melting temperature of aluminum alloys is substantially bellow that of ferrous alloys, higher heat inputs are required to weld aluminum because of its high specific heat.
High thermal conductivity makes aluminum very sensitive to fluctuations in heat input by the welding process. (Un-Quote)


lastly, this link http://www.key-to-metals.com/Article52.htm which the AL oxide melt temperature differs but more important is the oxygen and hydrogen interactions. (Quote) Aluminum is an active metal and it reacts with oxygen in the air to produce a thin hard film of aluminum oxide on the surface. The melting point of aluminum oxide is approximately 1926oC, which is almost three times the melting point of pure aluminum, 660oC. In addition, this aluminum oxide film, particularly as it becomes thicker, will absorb moisture from the air. Moisture is a source of hydrogen which is the cause of porosity in aluminum welds. Hydrogen may also come from oil, paint, and dirt in the weld area. It also comes from the oxide and foreign materials on the electrode or filler wire, as well as from the base metal. Hydrogen will enter the weld pool and is soluble in molten aluminum. As the aluminum solidifies it will retain much less hydrogen and the hydrogen is rejected during solidification. With a rapid cooling rate free hydrogen is retained within the weld and will cause porosity. Porosity will decrease weld strength and ductility depending on the amount. (Un-Quote).

----- Original Message -----
From: "Tesla list" <tesla@xxxxxxxxxx>
To: <tesla@xxxxxxxxxx>
Sent: Tuesday, June 21, 2005 5:22 PM
Subject: Re: Golka video: Ball Lightning in lab. WHAT?!!!!!


Original poster: "Mark Dunn" <mdunn@xxxxxxxxxxxx>



I saw the video, but did not hear the sound so don't know what
enlightening discussion took place on the video.
I've worked in the welding industry for 25 years and never realized
there was any debate about this.  I understand this to be nothing more
than a combination of the following:

1) The steel fragment is hot enough(~5000 Deg F) that combustion is
taking place - ie the steel is burning up.  The heat release from the
reaction is nearly sufficient to create a chain reaction.  The "nearly"
is why the reaction does not run to completion(the steel completely
consumed)and a grain is left over.  If it was Aluminum or Magnesium the
combustion would continue to completion.  Example: Fires, once started,
in an aluminum can recycling plant cannot be extinguished.  They run to
completion.  Only way to stop them would be to take away the oxygen.
Nothing is left when the fire finally goes out - except an aluminum
oxide coating all over everything.

2) A sphere of plasma created around the object by the high temperature
heating the Nitrogen/Oxygen air mixture.  Electrons jump clouds and
photons are emitted.  Remember that there are 3 ways(I think) to create
plasma: 1)Temperature 2)Pressure 3)Electrical Current.

I'm not a physics expert though, so things may be way more complicated
than I thought.

One could try the Golka experiment in an argon atmosphere and see if the
"shrinking" still occurs to learn more.

Mark