What material is C18000?

What material is C18000? 

 C18000 Background  

 In 1928, Michael G Corson of the Electro Metallurgical Co.   issued US patent 1658186A , “Copper Alloy and Process of Producing and Treating the Same” that  laid the ground work for an extremely useful copper alloy in the 21st century with high hardness , typically Rockwell B 95-102 and good thermal and electrical conductivity, typically 45-55% of pure copper. 

Today UNS C18000 is specified as a Class 3 (RWMA) material according the American Welding Standard J1.3/J1.3M:2020along side C17510, beryllium copper alloy with 0.5% Be. 

C18000 offers the best value in a Class 3 beryllium free grade suitable for most applications where C17500 or C17510 haves previously been specified. 


  C18000 Metallurgy, CuNiSiCr  

This alloy achieves its high strength and good conductivity from the precipitation of nickel and chromium silicide through heat treatments that first put nickel and chromium in solid solution of a copper-silicon matrix followed by precipitation hardening at about 900F that results in formation of nickel and chromium silicide and a high purity copper matrix.  

 During this final heat treatment the C18000 hardens by 20-30 points to Rockwell B 95 and  higher  while the electrical conductivity increases by over a factor of 2 from 20% IACS  to 45% IACS minimum. 


  C18000 Applications  

  • Plastic Injection molds and mold tooling components  
  • Injection molding plunger tips  
  • Sputtering target backing plates  
  • Resistance Welding electrodes, seam welding wheels, gun arms and other RW components, butt welding dies, cross wire welding dies 
  • Heat flux components in high energy physics particle accelerators 
  • Motor/generator components, rotor end rings, rotor wedges