Dynamic Responses of Nickel-Based Single Crystal Superalloy DD6 Blade

The aim of this article is to address the dynamic responses properties of the second-generation nickel-based single crystal superalloy DD6 with different orientations, rotor speeds, and temperatures, and this work can lay good foundation for predicting damage behaviors of the DD6 blade and starting with the application of gas turbine in aerospace. The finite element method was applied to investigate the dynamic characteristics of the DD6 blade with [001] and [111] orientations under different rotor speeds at 760, 980, and 1070 °C. On the basis of establishing the elastic-plastic constitutive model of single crystal alloy, the dynamic responses model of a DD6 blade was educed. As a result, the corresponding static and dynamic frequencies were analyzed for different temperatures, rotor speeds, and orientations. Comparison of the computational and experimental results shows the proposed model of the DD6 blade is effective. The analyses indicate that the natural frequencies of [111] orientation is higher than that of [001], and the effect of rotor speed on natural frequencies of [001] orientation is greater than that of [111]. In other words, the values of the natural frequency are increased with the elevated rotor speed, and the values of the natural frequency are decreased obviously with the elevated temperature.