Influence of tungsten and rhenium concentration on creep properties of a second generation superalloy

Creep properties at three different temperatures (1123, 1253 and 1373 K) for five single crystal alloys with varying Re and W content are presented. Tungsten content has been varied between 3.0 and 3.6 wt.%, rhenium between 2.3 and 2.9 wt.%. Creep properties, such as minimum creep rate, time to reach 1, or 2% strain and time to failure have been evaluated. For the low temperature regime, two parts of rhenium can be replaced by one part of tungsten. In the intermediate range, the ratio cW/cRe≈1.3 has to be fulfilled with the constraint that cRe≥2.3 wt.%. At high temperature the sum of W plus Re concentration determines the time to failure.