Aluminum-lithium alloy

Aluminum-lithium alloys are light and stiff, but they're pretty tricky when welding. The alloy is sensitive to too much heat and becomes brittle or cracks. You have to keep the material clean and strictly control the heat input, otherwise you'll warp the sheet. For the weld, you need a precise, focused arc and controlled cooling to keep the structure stable. And remember: these alloys don't like moisture, so keep the work surface and filler material dry.