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雷击铝合金的损伤特性和损伤机理是油罐等防雷保护研究的基础之一。为此,基于模拟雷电流试验方法研究了不同雷电流分量作用下储油常用铝合金材料铝3003的损伤特性和损伤机理,通过采用高分辨扫描电子显微镜(SEM)和X射线能量色散分析(EDS)对雷击3003铝合金的损伤形貌、组织形貌、损伤前后元素原子质量分数变化进行了观察和分析,结合不同雷电流分量的特性讨论了不同雷电流分量下合金的损伤特性和损伤机理。研究结果表明:首次短时间回击电流分量作用下,合金表面形成一层较薄氧化膜,膜层破碎萌生裂纹;回击间长持续时间雷电流分量作用下,合金损伤区第2相粒子密度增大且尺寸减小,过渡区第2相粒子密度明显减少,损伤区和过渡区界面出现树枝晶和带状晶界,合金受热熔化后在电应力作用下凝固不均匀产生裂纹;末次回击后长持续时间雷电流分量作用下,合金出现“过烧”现象,复熔程度加深,出现熔坑,合金损伤区形成了较多的析氢气孔,造成应力集中萌生裂纹。该研究结果可以为合金材料防雷性能的改进提供参考。
The damage characteristics and damage mechanism of the lightning strike aluminum alloy are one of the bases of mine protection research. Therefore, the damage characteristics and damage mechanisms of aluminum 3003, a common aluminum alloy material for oil storage under different lightning current components, were studied based on the simulated lightning current test method. High-resolution scanning electron microscopy (SEM) and energy dispersive X-ray analysis The damage morphology, microstructure and elemental atomic mass fraction before and after the damage were observed and analyzed in the 3003 aluminum alloy. The damage characteristics and damage mechanism of the alloy under different lightning current components were discussed based on the characteristics of different lightning current components. The results show that under the first short-term strikeback current component, a thin oxide layer is formed on the surface of the alloy and the film cracks and cracks are initiated. Under the long-term lightning strike current, the density of the second phase particles in the damaged zone increases And the size decreases. The density of the second phase particles in the transition zone decreases obviously. Dendrites and banded grain boundaries appear in the interface between the damaged zone and the transition zone. After the alloy melts under heat, the alloy cracks uniformly due to the electric stress. Under the action of time lightning current component, the alloy appeared “over-burning ” phenomenon, the degree of remelting deepened, and the crater formed. More hydrogen evolution pores were formed in the damaged area of the alloy, causing stress concentration initiation cracks. The results of this study can provide reference for improving the lightning protection performance of alloy materials.