magnesium

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This is probably a dumb question but can magnesium be welded? Just curious. I had a client ask today if I have ever worked with magnesium. I'm not sure what he has in mind. I have ground on, machined, etc mg....Yes I'm aware of it's combustion properties but in bulk it is hard to ignite. Just wondering.                                                                                                                                                                                                                                                                                                                                                                                        Never mind. Did a little research....How does one delite a post?Last edited by wagin; 07-17-2010 at 04:47 AM.Reason: researchMiller TrailBlazer 251Miller HF-250-1Miller MaxStar 150 STLHyperTherm PowerMax 380 plasmaLincoln PowerMig 180Millermatic 252Miller Diversion 180
Reply:For the benefit of anybody else who comes along and reads this, Wagin.  yes, you can TIG or oxy-acetylene weld Magnesium.  Not alot different than welding aluminum.  TIG arc flares green if you're welding magnesium.  I've had 2 people bring me parts to weld that I thought were aluminum.  Turned out they were magnesium.  If you try welding them with aluminum fillers, they fall apart.  It's very dissappointing, and I haven't figured out a good way to ID magnesium parts without trying to weld them first.First part was a coupler for a float used in concrete work.  Looked just like aluminum.  I found out later that lots of those concrete finishing tools are magnesium.  The second was a neighbor with a piece of trim from a pergola kit he bought at the big box store.  The trim was assembled from a collection of aluminum and magnesium parts.  I have no idea why.  Both parts took a bead, but immediately fell apart as soon as they cooled.  If anybody has a good method for non-destructively IDing magnesium parts, I'd love to hear it.Benson's Mobile Welding - Dayton, OH metro area - AWS Certified Welding Inspector
Reply:The acetic acid in vinegar will react with mag (bubbles away producing hydrogen) but the oxide layer protects Al alloys. A drop of 1% silver nitrate will result in a  black stain if the part is mag, again will not react with AlPretty much every mag part i've come across has been large enough that weight and/or appearence has given it up i.e. feels too light for an Al part and has a duller, greyer appearance. The clincher for me is usually when prepping the part in that mag machines sooo much more nicely than Al castings
Reply:Originally Posted by A_DAB_will_doFor the benefit of anybody else who comes along and reads this, Wagin.  yes, you can TIG or oxy-acetylene weld Magnesium.  Not alot different than welding aluminum.  TIG arc flares green if you're welding magnesium.  I've had 2 people bring me parts to weld that I thought were aluminum.  Turned out they were magnesium.  If you try welding them with aluminum fillers, they fall apart.  It's very dissappointing, and I haven't figured out a good way to ID magnesium parts without trying to weld them first.First part was a coupler for a float used in concrete work.  Looked just like aluminum.  I found out later that lots of those concrete finishing tools are magnesium.  The second was a neighbor with a piece of trim from a pergola kit he bought at the big box store.  The trim was assembled from a collection of aluminum and magnesium parts.  I have no idea why.  Both parts took a bead, but immediately fell apart as soon as they cooled.  If anybody has a good method for non-destructively IDing magnesium parts, I'd love to hear it.
Reply:Originally Posted by A_DAB_will_doFor the benefit of anybody else who comes along and reads this, Wagin.  yes, you can TIG or oxy-acetylene weld Magnesium.  Not alot different than welding aluminum.  TIG arc flares green if you're welding magnesium.  I've had 2 people bring me parts to weld that I thought were aluminum.  Turned out they were magnesium.  If you try welding them with aluminum fillers, they fall apart.  It's very dissappointing, and I haven't figured out a good way to ID magnesium parts without trying to weld them first.First part was a coupler for a float used in concrete work.  Looked just like aluminum.  I found out later that lots of those concrete finishing tools are magnesium.  The second was a neighbor with a piece of trim from a pergola kit he bought at the big box store.  The trim was assembled from a collection of aluminum and magnesium parts.  I have no idea why.  Both parts took a bead, but immediately fell apart as soon as they cooled.  If anybody has a good method for non-destructively IDing magnesium parts, I'd love to hear it.
Reply:Thanks Dave.  I'm red/green color blind, and so I have a really difficult time seeing the green flare from the TIG arc.  I also have an objection to leaving arc strikes anywhere I don't have to.Hotrodder's test with a little vinegar is much easier for me to observe and judge.  I should have remembered basic chemistry.  Thanks both of you for the suggestions. Originally Posted by dave powelsonDavid sez:  "If anybody has a good method for non-destructively IDing magnesium parts, I'd love to hear it.".........ID the magnesium, exactly the way you noticed--"TIG arc flares green if you're welding magnesium"Just lightly fire off the TIG torch on an area of the part that won't matter if there's a tinybit of melt from this.