View Full Version : magnesium
emo7207
08-15-2010, 04:45 AM
Hello all ! I have one question . Haw i weld magnesium ? Im from Bulgaria. Heге not big specialists .
SidecarFlip
08-15-2010, 10:54 AM
I didn't know you could. Magnesium woill burn if heated up with oxygen present, but I'll stand corrected.
emo7207
08-15-2010, 11:59 AM
http://www.youtube.com/watch?v=NeirmaCQUao and http://www.youtube.com/watch?v=Qx3G3ma8B7Y&NR=1 How do these guys? This my galery www.picasaweb.google.com/emo7207 Sorry --my english no good. I have motorcycle magnesium head - flat, and you should fix it. That is my problem! Thanks !!!
urch55
08-15-2010, 01:50 PM
Emo.
If that was indeed Magnesium it looked like they had a welding blanket around it, and I think it was being used to purged the welding area of oxygen and that would keep it from flaring up.
Are you sure you engine head is Magnesium and not cast aluminum.
The yellow flex tube looked like an exhaust duct, you can tell that when the helper held it close when the weldor used the die grinder.
Pangea
08-15-2010, 03:39 PM
The only difference in welding magnesium than aluminum is you hold a much tighter arc. AC with high frequency and keep that balled tungsten danger close to the puddle. the puddle will be pushed away and you will actually have the tungsten below the surface plane of the parent metal.
Other than that, it's just like aluminum.
Roger
08-15-2010, 06:24 PM
wikipedia has nice short section on what you really need to know on this linked page.
http://en.wikipedia.org/wiki/Gas_tungsten_arc_welding
Don't use water to put out magnesium fire because water breaks down in extreme heat of magnesium fire releasing Oxygen making fire worse.
Use only dry chemical fire extinguisher rated for magnesium fire. US Navy used Purple K extinguisher.
Main problem you will have is oil soaked into metal pours that contaminates weld.
Aerometalworker
08-16-2010, 03:39 PM
I have tig and gas welded a couple of the mag alloys, and along with a slight "mushy" feel of the puddle, about the only thing to watch for is the larger ammount of thermal expansion vs aluminum. Preheating castings of course helps greatly, as does planning your welds. The ignition temperature of magnesium is above the melting point, so there is no reason to purge the area of oxygen. When gas welded just a normal torch is used with magnesium filler and magnesium flux. Nothing special.
taylorkh
08-16-2010, 04:08 PM
US Navy used Purple K extinguisher. Purple K is not rated Class D for combustible metals. It is great for petroleum based flammable or combustible liquids - Class B. When I was in the Nuclear Navy we had Class D rated extinguishers available - but I can not tell you for what metal :D (no, not Uranium) Same holds true in the commercial nuclear field.
So here is a fire protection trivia question... What is the difference between a flammable and a combustible liquid?
Ken
urch55
08-16-2010, 04:41 PM
So here is a fire protection trivia question... What is the difference between a flammable and a combustible liquid?
Ken
Combustible = It's burnable. Flammable = Easy to catch on fire, (ignite)....
emo7207
08-20-2010, 11:13 AM
Thank you all! Hard to find a complementary wire in Bulgaria. Another vareyant Ill try! Thanks ! p.s I looking for job
Purple K is not rated Class D for combustible metals. It is great for petroleum based flammable or combustible liquids - Class B. When I was in the Nuclear Navy we had Class D rated extinguishers available - but I can not tell you for what metal :D (no, not Uranium) Same holds true in the commercial nuclear field.
So here is a fire protection trivia question... What is the difference between a flammable and a combustible liquid?
Ken
Whiskey is flammable, Tequila is Combustible.... :D