Advances & challenges in the manufacture of nickel-base superalloy and titanium alloy ingots for high performance wrought applications

摘要

The drive for higher quality combined with lower costs to help meet the demands of the newer turbine engines has led to continuous improvements in melting processes. Higher quality entails improved cleanliness and reduced segregation. Emphasis for superalloys has been on the remelt processes VAR (Vacuum Arc Remelting) and ESR (Electroslag Remelting). Improved VAR control systems, which employ multiple estimates of the arc gap, are under development through the Specialty Metals Processing Consortium (SMPC) and show considerable potential for more stable melt rate control.