This standard specifies a quantitative test method for evaluating the surface hydrophilicity (wettability) of aluminum and aluminum alloy foils. The core principle involves using the contact angle method, where the hydrophilicity is precisely assessed by measuring the contact angle formed by a water droplet on the aluminum foil surface. The standard details requirements for sample preparation, cleaning, and conditioning prior to testing, and defines the standard test environment (temperature 23±2°C, relative humidity 50±10%) to ensure result comparability. The key instrument required to perform this method is a contact angle measurement device, which employs a precision injection system to form a standardized water droplet on the sample surface and utilizes a high-resolution imaging and image analysis system to automatically determine and calculate the static contact angle.