CUNI 90/10 Buttweld Class 200
ANSI B16.9
Cupronickel (also known as copper-nickel and CUNI) is an alloy of copper that contains nickel and strengthening elements, such as iron and manganese.
Copper Nickel C706 is also known as Copper Nickel 90/10 because it is made up of 10% nickel or as ASTM B466 and ASME SB466. CUNI C706 is known for its moderate strength, weldability, and formability.
The inclusion of controlled quantities of iron and manganese also give the CUNI 90/10 alloy an extraordinary resistance to general corrosion and stress cracking, as well as to erosion and impingement due to turbulent water containing air bubbles and silt flowing at high velocities.