温度对粉末高温合金夹杂热力耦合损伤行为的影响

Effects of Temperature on Damage of Powder Super Alloy Caused by Inclusions under Thermal-mechanical Coupling Condition

建立了夹杂及基体的三维有限元模型。研究了热力耦合条件下粉末高温合金所含夹杂对基体材料的损伤规律,并与现有二维有限元模型模拟结果对比,验证了本模型的准确性。结果表明:在400~700℃,夹杂/基体界面温度场分布呈一定规律;界面耦合应力分布中机械应力占据主导,随着温度的升高,热应力对耦合应力贡献程度与温度成一定的增长规律。将本模型进行常温分析,与现有二维模型的常温分析结果进行定量对比,并计算相对误差。Mises应力相对误差为0.9%,塑性应变相对误差为7.7%,两者误差均保持在允许范围内,这验证了本模型的准确性。

A three-dimensional finite element model of inclusions and matrix was established.The damage law of powder super alloys inclusions on the matrix materials under thermo-mechanical coupling conditions was researched.The accuracy of the model was verified by comparing with the existing two-dimensional finite element model simulation result.The simulation results show that at 400-700℃,the temperature field distribution of the inclusion/matrix interface is regular;the mechanical stress dominates the coupled stress distribution.As the temperature increases,the contribution of thermal stress to the coupled stress is quadratic function as temperature increasing.The model under normal temperature was analyzed,which were quantitatively compared with the normal temperature analysis results of the existing two-dimensional model,and the relative error was calculated.The relative error of Mises stress is 0.9%,and the relative error of plastic strain is 7.7%.Both the errors are kept within the allowable range,and the accuracy of the model is verified.