定向凝固涡轮叶片的晶体热粘塑性变形与损伤分析

采用一种考虑损伤的单晶体热—粘塑性变形本构模型和迭代求解数值方法,可以描述单晶在变温过程中的应力应变关系,还可以描述单晶在晶体滑移机制控制下的蠕变变形和孔洞型损伤;考虑定向凝固高温涡轮叶片的柱晶结构,应用本文模型和算法对包含若干个柱晶晶粒的定向凝固气冷涡轮叶片进行不均匀温度场下的变温热粘塑性蠕变和损伤分析。分析结果表明:该涡轮叶片在本文考虑条件下处于较低的应力水平,500小时叶尖蠕变伸长低于0.006mm。 

Crystalline Thermo Visco-Plastic Deformation and Damage of Directionally Solidified Turbine Blade

A single crystalline thermo visco-plastic constitutive model associated with an iterative algorithm was introduced.They can be used to describe the stress-strain relationship of a single crystal in an anisothermal process,and also to describe the crystalline creep and damage of a single crystal under slipping mechanism.This model and algorithm were applied to the analyses of anisothermal visco-plastic creep and damage of an air-cooled directional solidification turbine blade taking into consideration of the column crystalline grain structure.The analysis show that under the condition considered in the present paper,the air cooled directional solidification turbine blade is under going a relatively low stress,and the induced blade tip creep elongation is not more than 0.06 mm in 500 working hours.