Vacuum Applications Beryllium Copper Bellows Nomenclature Bellows Movements Standard Tolerances Multiply or Laminated Bellows Neck Trims Explanation of Tabulated Data Ordering Instructions Beryllium Copper The beryllium copper alloys have high thermal and electrical conductivity similar to pure copper. It can be readily joined by resistance and fusion welding, brazing and soldering. The material is nonsparking, nonmagnetic; it has high galling resistance, and maintains its strength and ductility at cryogenic temperatures.