Galvanizing is the process of joining the two metals by subjecting them to high temperatures, often over 300 degrees Celsius. When the metals are heated to this degree they become pliable and ductile, and this is where the idea of galvanized steel came about. When you buy a hot dip galvanized steel piece, it will have been dipped into a vat of water that has been filled with an acid solution and then exposed to an electric current. The galvanized steel has been given a color of either red blue or green due to the dye that has been used to color the metal.
The reason why the color galvanizing works is because the metal has been negatively affected by rust before it has even had a chance to reach the eye of the buyer. The galvanized zinc coating on the product ensures that the product remains durable and rust resistant even after it has been subjected to high temperatures. Hot dip galvanized steel tends to rust more quickly than standard galvanized steel because of the rapid increase in temperature. Standard galvanized steel tends to rust slower because of the chemical reactions which take place during the zinc coating, making the coating to last much longer. There is also less chance for galvanized steel to corrode when hot dip galvanized is used for decorative purposes.
Hot dip galvanized is the most common form of galvanized steel. It contains three different types of zinc, ranging from plain galvanized to yellow chromate. Plain galvanized has no coloring because it contains only the active material, which in this case, is the Zinc. The other two are colored to achieve a better visual effect: yellow chromate is the standard type and red chromate is used for decoration.
Yellow chromate is the standard galvanized form, which makes it more affordable than other forms. It offers better color matching than the seven-color galvanized variety and therefore is preferred by manufacturers. Yellow chromate has good corrosion resistance, which is one of its many benefits. Since the material is resistant to corrosion, it is a cheaper solution when compared to seven-color galvanized.
Red is a popular choice for decorative applications. Its rich red hue is also suitable for aesthetic purposes, though not as good as the other two types. Red is a good conductor of heat and therefore can be used for plating bodies or parts that need protection from too much heat, such as a hot plate. The material will not corrode over time, which is why it is perfect for body plating. A part with a red plating surface is highly conductive and therefore is able to transfer energy to its surroundings easily. However, it has poor corrosion resistance, which is why it is not used as frequently as the other two.
Zinc is another metal often used for decorative applications. Though it lacks some of the color plating properties of its steel counterparts, it does possess some positive attributes. It is extremely durable, resists corrosion and does not discolor. The zinc surface is highly conductive and this makes it perfect for galvanizing bodies or parts that need a lot of energy to transfer.
It is generally accepted that hot dip galvanizing is the best solution for high-carbon steel or alloyed steel. The problem is that hot dip galvanizing cannot be used on non-carbon steel, as the process will not achieve full corrosion protection. Some of the options that you have for corrosion protection include hot dip galvanizing and hot dip painting. Hot dip galvanizing uses an extremely hot forming environment, which can cause extreme wear and tear to fabricated steel, particularly around fasteners.
On the other hand, hot dip galvanizing works well on steel with a lower carbon content. The biggest advantage of hot dip galvanizing is that it offers corrosion protection. However, it should be noted that in practice, the level of corrosion protection offered by hot dip galvanized steel is far less than that provided by cold dip galvanized steel or cold dip painting. Thus, if you are looking for corrosion protection, it might be better to opt for another process, as compared to using hot dip galvanizing. Other popular methods for corrosion protection include hot dip galvanizing, cold dip galvanizing, galvanized steel, electroplating and coatings.