Introduction of Steel Enamel Ground Coat
Ground coat is enamel frit directly coated on the metal substrate, ground coat on the enamel products of the internal quality and appearance of the quality plays a decisive role.
The main requirements of the enamel ground coat are as follows.
① can be well combined with the steel substrate.
② can be a good combination with the cover coat.
③ isolate the metal body and cover coat, to avoid the quality problem casued by the contact of metal body and cover coat.
④When the enamel products thermal expansion and contraction, can play a buffer role between the metal body and cover coat.
⑤ In order to prevent or reduce the damage caused by various stresses on the enamel products, reduce the bubbles on the enamel cover coat layer, and ensure that the products have a good and smooth appearance.
There are many kinds of enamel ground coat, and many ways to classify. According to the material of metal blank can be divided into steel enamel ground coat, cast enamel iron ground coat, stainless steel enamel ground coat, copper and copper alloy enamel ground coat, aluminum and aluminum alloy enamel ground coat, etc.; according to the classification of dense agent, can be divided into enamel cobalt ground coat, enamel nickel ground coat, enamel cobalt nickel ground coat, enamel antimony ground coat, enamel antimony molybdenum ground coat.
Cobalt ground coat is cobalt oxide as the dense agent. The introduction of cobalt oxide in the ground coat at 0.5% can achieve good adhesion strength. When designing the ground coat, the amount of cobalt oxide introduced depends on the adhesion requirements or the thickness of the steel plate. The introduction of cobalt oxide is 0.5%~0.8% in the ground coat of daily-use enamel; the introduction of cobalt oxide is 0.2%~2.6% in the ground coat of cast iron sanitary ware or acid-resistant industrial enamel.
Nickel ground coat is the ground coat with nickel oxide as the main adhesion agent. Nickel oxide is slightly worse than cobalt oxide, so the introduction amount is slightly higher than cobalt oxide in ordinary ground coat, generally 1%~2%.
Cobalt-nickel ground coat is a bground coat that introduces both cobalt oxide and nickel oxide as adhesives. This kind of ground coat has a strong adhesion ability, and its superiority is that the introduction of a small amount of adhesion agent in the ground coat can achieve a good adhesion effect.
Antimony ground coat is the ground coat with antimony oxide as the main adhesion agent. Generally, a part of antimony oxide is melted in the ground coat first, and then a part of antimony oxide is added when the ground coat is ground into a slurry. Antimony ground coat agrees to have better adhesion strength.
Antimony-molybdenum ground coat is the ground coat that introduces a certain amount of antimony oxide and molybdenum oxide as the adhesion agent at the same time. The introduction of antimony and molybdenum can be used to melt and grind the method of addition. Practice has proved that the adhesion ability of antimony-molybdenum ground coat is no less than that of cobalt ground coat and nickel ground coat, but the cost is lower than that of cobalt ground coat and nickel ground coat.
The main requirements of the enamel ground coat are as follows.
① can be well combined with the steel substrate.
② can be a good combination with the cover coat.
③ isolate the metal body and cover coat, to avoid the quality problem casued by the contact of metal body and cover coat.
④When the enamel products thermal expansion and contraction, can play a buffer role between the metal body and cover coat.
⑤ In order to prevent or reduce the damage caused by various stresses on the enamel products, reduce the bubbles on the enamel cover coat layer, and ensure that the products have a good and smooth appearance.
Cobalt ground coat is cobalt oxide as the dense agent. The introduction of cobalt oxide in the ground coat at 0.5% can achieve good adhesion strength. When designing the ground coat, the amount of cobalt oxide introduced depends on the adhesion requirements or the thickness of the steel plate. The introduction of cobalt oxide is 0.5%~0.8% in the ground coat of daily-use enamel; the introduction of cobalt oxide is 0.2%~2.6% in the ground coat of cast iron sanitary ware or acid-resistant industrial enamel.
Nickel ground coat is the ground coat with nickel oxide as the main adhesion agent. Nickel oxide is slightly worse than cobalt oxide, so the introduction amount is slightly higher than cobalt oxide in ordinary ground coat, generally 1%~2%.
Cobalt-nickel ground coat is a bground coat that introduces both cobalt oxide and nickel oxide as adhesives. This kind of ground coat has a strong adhesion ability, and its superiority is that the introduction of a small amount of adhesion agent in the ground coat can achieve a good adhesion effect.
Antimony ground coat is the ground coat with antimony oxide as the main adhesion agent. Generally, a part of antimony oxide is melted in the ground coat first, and then a part of antimony oxide is added when the ground coat is ground into a slurry. Antimony ground coat agrees to have better adhesion strength.
Antimony-molybdenum ground coat is the ground coat that introduces a certain amount of antimony oxide and molybdenum oxide as the adhesion agent at the same time. The introduction of antimony and molybdenum can be used to melt and grind the method of addition. Practice has proved that the adhesion ability of antimony-molybdenum ground coat is no less than that of cobalt ground coat and nickel ground coat, but the cost is lower than that of cobalt ground coat and nickel ground coat.