FGH95粉末高温合金裂纹闭合数值模拟

Numerical Simulation of Crack Closure in FGH95 Powder Metallurgy Superalloys

夹杂、温度和远场应力是影响粉末高温合金材料断裂性能的重要因素。本文建立了考虑裂纹面接触的含夹杂裂纹体有限元模型 ,计算了夹杂、温度和远场应力对裂纹闭合的影响。计算结果分析表明 :当夹杂与基体未脱开时 ,夹杂对裂纹的张开应力几乎没有影响 ,而裂开的夹杂可显著提高裂纹的张开应力 ;均匀的温度场能显著降低裂纹的张开应力 ;远场应力越大 ,裂纹张开应力越大。

Temperature,inclusion and remote stress are the most important reasons that affect the fracture feature of powder metallurgy(PM)super-alloys.An finite element model which takes the contact between crack lines into account was built,and the numerical simulation of the effects of inclusion,temperature and remote stress on crack closure has been carried out.The opening stress for the growing crack was determined.The calculation results show that the perfectly bonded inclusion has little effects on the opening stress of the crack,while the debonded inclusion will increase the opening stress.The uniform temperature field has decreased the opening stress obviously.The opening stress will increase with the rise of the remote stress.