A two-damage-variable creep constitutive model was used to analyze the creep deformation of nickel-based single crystal turbine blades.Based on multidisciplinary design optimization theory

the crystallographic orientation optimization was performed by ASA(adaptive simulation annealing) and NLSQP(non-linear sequential quadratic programming) algorithm.The analysis results show that controlled orientation and uncontrolled orientation have profound influence on creep deformation of single crystal turbine blades.The minimal radial displacement of blade tip is 0.07774mm

when one of uncontrolled crystal orientations is 76.2° in one dimensional optimization state.The optimization amplitude is 2.0%.The minimal radial displacement of blade tip is 0.07378mm

when two uncontrolled crystal orientations are 63.7° and 81.4°

respectively in two dimensional optimization states.The optimization amplitude is 5.4%.The radial displacements of blade tip are 0.07929mm and 0.09352mm when the controlled orientations are 0° and 10°

respectively.The amplitude variation is 17.9%.