GB/T 9989.2 - 2015 is the second part of the series of standards for the determination of chemical erosion resistance of enamels. It specifies the determination method for the chemical erosion of enamels against boiling acids, boiling neutral liquids and their vapors. The standard specifies the test equipment, details the sample preparation process, describes the operation steps of placing enamel samples in boiling acid, neutral liquids and their vapor environments, and evaluates the corrosion resistance performance according to specific criteria by observing the erosion phenomenon. This standard provides a basis for evaluating the corrosion resistance of enamels in high temperature chemical environments, and helps to ensure the mass and durability of enamel products in relevant scenarios.