Aluminum-Magnesium Cast Alloy Structure

AlMg cast is highly seawater-resistant and can generally be welded, but you must be careful: it tends to crack when hot if you heat it too much or cool it too quickly. Before welding, the material should be clean and dry, otherwise you'll get pores in the weld. Let the weld cool slowly to avoid stress buildup. If you work with TIG and keep the heat under control, you'll manage.