国产 综合 日韩_日韩免费a级毛片无码a∨_欧美 亚洲 日韩 在线综合_亚洲寂寞寡妇影院51_国产av毛片大全_亚洲∨国产V综合V精品_免费看黄软件分享的内容是很丰富的_久久精品日韩欧美_后进白嫩翘臀在线视频_欧美一级免费黄片

What are the main characteristics of "memory" alloys?

[ 信息發(fā)布:本站 | 發(fā)布時間:2019-09-12 | 瀏覽:2568 ]


In order to implement the lunar antenna plan, a large diameter parabolic antenna must be transported to the moon ball by an aerospace aircraft. However, how can such a large antenna be equipped with a very small space shuttle inside the person? The U.S. Aerospace Administration uses the shape memory alloy technology. This alloy material will undergo significant changes in its physical properties under specific temperature conditions. It is an alloy with a unique shape memory function. After the initial deformation of the alloy, When the pre-deformation shape memory alloy is heated so that the temperature exceeds the phase transition temperature of the alloy, the shape memory alloy material will return to the shape before the deformation. NASA scientists made a parabolic lunar antenna from a shape memory alloy at room temperature, then kneaded it into a small group of less than 5 cm in diameter and launched it into the moon in the capsule of Apollo 11. Heated by sunlight on the moon surface to restore it to its original parabolic shape. This will allow the large antenna to be transported in a space limited space shuttle cabin.