I have a 50 year old forged magnesium alloy wheel apparently marked AS161, which I have been led to believe is AS1.61 - not dissimilar to this picture here. So I assume 1.6% aluminium and 1% silicone - sound reasonable? A spoke is cracked and I'd like to weld it. What would be the correct heat treatment for this alloy, to relieve welding-related stresses?
I've seen circa 340 Celcius for annealling to relieve stresses. And I've seen holding at 175 Celcius for circa 24 hours to harden. Then I'm aware that the magnesium will already have naturally hardened over time. And I've seen a specific recommendation for welding stress relief, to hold for fifteen minutes to one hour at between 130 to 260 Celcius, depending on the alloy composition, but I don't have a recommendation for this specific alloy.
I'm aware magnesium burns in water.