Development of a New Alloy for Directional Solidification of Large Industrial Gas Turbine Blades

Abstract

A nickel-base superalloy for directional solidification (DS) of industrial gas turbine blades was developed based on alloy IN792 with approximately 12 mass % Cr.From preliminary test results a temperature gain in stress-rupture strength of 30 K can be expected compared to Re-free aero engine alloys with columnar grains.This significant strength improvement can be achieved by adding 2 to 3 mass % Re in the group of 12 mass % Cr alloys.With balanced Cr-, Al-, and Ti-contents they also exhibit superior hot corrosion resistance compared to typical high Al / low Cr / low Ti aero engine alloys.The castability for large blades was proved.