Influence of rhenium and tungsten on the microstructure and performance of GH4169 alloy through heat treatment

The microstructure and performances of GH4169 nickel (Ni)-based alloy were studied after adding the elements rhenium (Re) and tungsten (W) and then conducting heat treatment. The alloy containing the element rhenium showed less delta phase after heat treatment. For both alloys containing the element tungsten and the GH4169 alloy without any element, the d phase and rectangular carbide were all precipitated after the heat treatment. The creep rupture life of the alloy added with the element rhenium was higher than that of the alloy added with the element tungsten at a high temperature. When a mixture of 75% sodium sulfate (Na2SO4) and 25% sodium chloride (NaCl) was applied at 950 degrees C under the same conditions, the thermal corrosion resistance of the nickel-based alloy containing rhenium was obviously better than that of the nickel-based alloy containing tungsten. The hot-corrosion resistance of the GH4169 alloy without adding any element was slightly better than that of the alloy with tungsten.