Enamel frits can be divided into cast iron enamels, steel enamels, stainless steel enamels, aluminum enamel frits, etc. according to the metal substrate.

Stainless steel enamel frit: 304 stainless steel base material is suitable, and 316 is also useful. Stainless steel needs sanding treatment, degreasing treatment without adhesion. Stainless steel enamel is divided into ground coat, cover coat and direct on enamel. Stainless steel enamel can also be colorful.

Steel enamel frit: Steel plate enamel ground coat can be divided into cobalt ground coat (cobalt oxide), nickel ground coat (nickel oxide), cobalt nickel ground coat, antimony ground coat (antimony oxide) and antimony molybdenum ground coat according to different adhesives (antimony oxide and molybdenum oxide), the main requirement is that the enamel ground coat can be well adhered to the steel plate. The steel plate cover coat is the enamel coated on the ground coat, which can be divided according to the opacifying agent, such as titanium cover coat, tin cover coat, zirconium cover coat, etc. It is required that the enamel products should achieve good whiteness and gloss after firing, and be able to adapt to A certain degree of acid resistance and oxidation resistance is required.

Cast iron enamel: cast iron ground coat, cast iron cover coat, colored enamel, matte enamel, etc.

The cast iron body is generally sanded, sandblasted, and polished surface residues; some are sanded after annealing and tempering; some are not annealed, directly sanded and then enamelled. The quality of the enamel made after annealing is only stable, and those that are not annealed are prone to defects such as pinholes, blisters, porcelain bursts, and poor porcelain surfaces. The current matte cast iron enamel generally does not use the annealing process, but is directly sanded and enameled. Because the matte porcelain layer is thinner, generally 80-120um has better air permeability than bright enamel, and the porcelain surface does not need to be smooth, so the quality is acceptable.

Aluminum enamel: The aluminum body cannot be degreased, and the general method is burning oil. Remove oil at 550 degrees, and quickly remove surface impurities with 5-10% nitric acid solution. Rinse with water and dry for later use. Aluminum enamel grinding does not use clay, and sodium silicate solution is used as suspending agent. The firing temperature is between 550-600 degrees. Aluminum enamel can also be printed with designs and colors after the primary titanium white enamel is made, and fired again. The soleplate of high-grade electric irons is aluminum enamel.