Yeild ocuurs then plastic deformation then rupture under cold work of steel the rupture allows leakage which relieves the pressure in a tank,
But is it better to use aluminum, which is a lighter metal, because the cold work becomes brittle result of coldwork.
Explain more about brittleness, and is it better to use aluminum? How does aluminum behave under a pressurized tank, the point is to avoid catastrpic failure.