Cause analysis of "mildew" on aluminum alloy frame for photovoltaic module
The cause of "mildew" on aluminum alloy frame for photovoltaic module is analyzed. Methods: the removed "mildew" part and normal part of aluminum alloy frame were studied by substrate composition analysis, oxide film thickness analysis, scanning electron microscope micro morphology and energy spectrum analysis. Results: it was found that the "mildew" was caused by the spot corrosion of aluminum alloy, which was the precipitate of aluminum alloy after corrosion. Conclusion: the humid environment can lead to the spot corrosion of aluminum alloy, and the halogen ion on the sample surface can accelerate the corrosion effect. Cutting off the environmental conditions of halogen ion can reduce the occurrence of corrosion and prevent the fracture of photovoltaic modules after installation.
