论文部分内容阅读
以Al-6Mg-0.8Zn-0.5Mn-0.2Zr-0.2Er合金为基础,对该材料的冷轧态,温轧态,完全退火态进行拉伸测试和疲劳裂纹扩展速率测试。运用电子背散射衍射(EBSD),透射电镜(TEM),扫描电镜(SEM)对合金的原始组织、疲劳断口、裂纹扩展路径进行观察,研究微观组织对材料拉伸性能及疲劳裂纹扩展速率的影响。结果表明:温轧态屈服强度高,裂纹扩展抗力大,实现了高强高耐损伤性能的匹配。这主要是由于温轧态轧制过程中发生动态回复,位错缠结规整化,具有较多的亚晶界,该种组织模式对材料的屈服强度和疲劳裂纹扩展抗力均有提高。
Based on the Al-6Mg-0.8Zn-0.5Mn-0.2Zr-0.2Er alloy, the tensile test and fatigue crack growth rate test of the material in cold-rolled, warm-rolled and fully annealed condition were carried out. The effects of microstructure on the tensile properties and fatigue crack growth rate of the alloy were investigated by using electron backscatter diffraction (EBSD), transmission electron microscopy (TEM) and scanning electron microscopy (SEM) on the original structure, fatigue fracture and crack propagation path. . The results show that the yield strength is high and the crack propagation resistance is large in the warm-rolled state, which achieves the matching of the high-strength, high-resistance and damaging properties. This is mainly due to the dynamic recovery during the rolling of hot-rolled state, the dislocation entanglement regularization, with more subgrain boundaries, and this kind of microstructure mode has an improvement on the yield strength and fatigue crack propagation resistance of the material.