With the development of aerospace technology

spacecraft materials are developing toward directions of reducing structural weight

improving performances and decreasing manufacturing costs

while the light weight is an important factor to impede its development.The Mg-Li alloys are considered to be the lightest structural materials

and have the high specific strength and stiffness characteristics.These alloys have the greatly potential application in the fields of aeronautics

astronautics and weaponry

particularly in the deep space exploration and micro-nano satellites.The researching status

application prospect in the astronautics and the key problems of Mg-Li alloys were reviewed.