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The corrosion characteristics of Sn‐3.0Ag‐0.5Cu solder under polyvinyl chloride (PVC) and polyethylene (PE) fire smoke atmospheres were investigated by weight loss method and surface characterization techniques. The corrosion kinetics results of 15‐day tests show that the mass loss of Sn‐3.0Ag‐0.5Cu solder in PE smoke is much lower than that in PVC smoke. The former shows no significant variation during the test. In contrast, the latter increases rapidly first and then presents a slow exponential increase. Microstructure analysis indicates that no obvious corrosion product appeared in PE smoke. Nevertheless, the corrosion products in PVC smoke grow larger first and then become smaller and denser. The possible growth process of corrosion products is that grain growth dominates the formation of the corrosion products at the initial stage and then the nucleation process is predominant. Furthermore, the corrosion mechanisms of Sn‐3.0Ag‐0.5Cu solder in the different fire smoke are also analyzed. Stannous oxide and stannic oxide are regarded as the corrosion products under both PE and PVC smoke atmospheres, while Sn21Cl16(OH)14O6 is only observed under PVC smoke atmosphere.

Three hundred and four stainless steel and 6061 aluminium alloy samples were exposed to different concentrations of smoke generated by polyvinyl chloride in high humidity. The corrosion kinetics of 304 stainless steel and 6061 aluminium alloy under smoke were found to obey the power function and a linear rule, respectively. Pitting corrosion in smoke became increasingly obvious with exposure time. Surface morphology and chemical compositions of corrosion products were analysed by scanning electron microscope, energy dispersive spectroscopy and X-ray photoelectron spectroscopy. Possible corrosion mechanisms were proposed and compared. All the analysis helps to provide basic information for the determination of smoke damage and timely rescue after fire.

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