scrap heap         
noun uk/ˈskræp ˌhiːp/ us/ˈskræp ˌhiːp/
 [ C ]废物堆(尤指废金属堆) 
a pile of old, unwanted things, especially pieces of metal
  [ S ](思想或人)无人感兴趣的 
If an idea or person is on the scrap heap, people are no longer interested in them.
  Some people believe that Communism has been relegated/consigned to the scrap heap of history.
 Many top class players end up on the scrap heap after a short career. 许多顶级选手很快就被人遗忘了。