目前标准鎂合金的比重約为1.8。在一些美国宇宙飞行系統中最近采用了一种比重約为1.35的LA 141 A鎂-鋰合金。宇宙飞行設計师确信,用这种輕质的特种合金材料能使导彈和宇宙飞行器結构的重量减輕25％之多。在鎂协会第十八届年会上,爱里欧特,威尔内(Elliott wilner),在他的以“LA141A——宇宙飞行器用 At present, the proportion of standard magnesium alloy is about 1.8. In some U.S. space flight systems recently a LA 141 A magnesium-lithium alloy with a specific gravity of about 1.35 has been used. Cosmic flight designers are convinced that using this lightweight specialty alloy can reduce the weight of missiles and spacecraft structures by as much as 25%. At the 18th Annual Meeting of the Magnesium Society, Elliott Wilner, in his book "LA141A - Spacecraft