应变速率对单晶高温合金中温拉伸性能的影响

Effect of strain rate on tensile properties of single crystal superalloy at intermediate temperature

研究了应变速率对一种单晶高温合金760和850℃拉伸性能的影响,分析了试样的断口形貌和断裂组织特征。结果表明,随着应变速率的增加,合金的中温拉伸强度稍有增加,伸长率稍有减小。合金中温拉伸性能对应变速率的敏感性非常小。合金中温拉伸断裂机制为类解理断裂,随着应变速率的增加,解理面的总面积减小,滑移带间距变窄。

Effect of strain rate on tensile properties of single crystal superalloy at 760 ℃ and 850 ℃ was investigated. The fracture surface and ruptured microstructure of the alloy were analyzed. The results show that with increasing of the strain rate,the tensile strength slightly increases and elongation slightly decreases at intermediate temperature. It indicates that the tensile properties of the alloy has very small sensitivity with strain rate. The tensile fracture mechanisms of the alloy is quasi-cleavage fracture at intermediate temperature. The total area of cleavage plane and the space of slip band decrease with increasing of the strain rate.