Scandium metal (Sc) is a chemical element with the symbol Sc and atomic number 21.  ItIs a soft, silvery white transition metal, often mixed with gadolinium, erbium, etc in low production, about 0.0005% in the earth's crust.  as one of the 17 rare earth elements, scandium has been discovered for more than one hundred years.  since the 1970s, scandium has entered the stage of application and development,  and has become one of the most active emerging materials in recent years.        Russia's research on scandium is more systematic, which has been used in Migg, Jacques, Tu series of fighter jets and passenger planes.  In 2015, the European Commission issued the "European Metallurgical Road map: Producers and End-Users outlook" involving a total of 9 metal elements, including in the transport industry proposed to study "aluminum magnesium scandium alloy weldability";  In February 2018, the United States released a list of 35 key minerals, scandium as an industrial raw material is among them.  There are 166 new materials in the First Application Demonstration Guidance Catalogue (2018 Edition) of Key New Materials released by the Ministry of Industry and Information Technology, among which there are 3 new materials involving scandium and its products.