Effect of decomposition products from electrical insulation on metal and metal finishes

The foregoing presents evidence of corrosion caused by the heat decomposition of electrical insulation materials. The temperatures used with Class O and A type materials were necessarily somewhat severe in order to include the additional heat caused by the operation of electrical or electronic systems within closed containers. The results show: 1. That extracted materials from PVC sleevings and also vapors from PVC in inclosed areas are highly acidic and may cause corrosion due perhaps to improper stabilization. 2. That cadmium and zinc are rather easily corroded by many insulation materials, especially plastic sleevings. 3. That sealing (potting) compounds can cause severe corroding of copper. 4. That the heat resistant molded plastics used in this report were not effectively stabilized. 5. That aluminum and anodized aluminum were relatively uneffected by contact or vapors from the insulation materials tested.