acid galvanizing

Acidic Zinc Plating

Acidic zinc plating, also known as white (or semi-bright) zinc, is a process that involves the immersion of steel or other low-alloyed zinc parts into a bath of zinc sulfate and ammonium chloride or ammonium sulfate. This is a commonly used method of zinc plating and is used in a variety of industries ranging from automotive to electronics. The process provides excellent corrosion protection and is a good choice for parts that will be exposed to harsh environments.

The acidic zinc plating process begins with the formation of zinc sulfate and ammonium chloride or ammonium sulfate in a water bath. The parts are then placed in the plating bath and an electric current is passed through the solution. This causes a chemical reaction between the zinc ions and the steel parts, resulting in a layer of zinc being plated onto the parts.

Once the desired thickness of the zinc layer is achieved, the parts are rinsed and then dried. After drying, the parts are subjected to a thermal treatment to harden the zinc and provide increased corrosion protection. This thermal treatment can take 20 to 30 minutes depending on the material and thickness of the coating.

Once the processing is complete, the parts can be inspected to ensure that the desired amount of plating has been achieved. In general, acidic zinc plating is used when an environment has a tendency to turn steel parts a white or gray color. This plating process provides a corrosion-resistant coating that will protect the surface of the part from rusting.

The benefits of acidic zinc plating are numerous. It offers excellent corrosion protection, is relatively inexpensive, and can be applied to a variety of materials. It also provides a clean finish that has a high level of aesthetic appeal. It is an ideal choice for parts that will be exposed to corrosive environments.

The drawbacks of the process are that it is slow and requires the use of hazardous chemicals. Additionally, the parts must undergo a series of steps to achieve the desired thickness, which can increase costs and lead time.

Despite these drawbacks, acidic zinc plating is an effective method of protecting metal parts against corrosion. It is an economical option that can provide a high level of protection in a variety of environments. Its advantages make it a preferred choice for many industries.

Acid pickling is a commonly used method for hot-dip galvanizing. It is a common method to remove iron oxide on the surface of steel home and fasten the rust rate of galvanizing.

The process of acid pickling is simple, it is immersing the workpiece into acid soaking liquid. The acid liquid is usually composed of nitric acid and hydrochloric acid.And the concentration of the acid depends on different workpieces.

Once the workpiece is dipped into the acid liquid, the acidic reaction between the acid and the material takes place, which forms the new pickling layer on the surface of the workpiece. The pickling layer is obtained through acid etching, which increases the surface of the workpiece, making it more uniform and in contact with the hot-dip galvanizing layer.

In addition to pickling, phosphating is also necessary for hot-dip galvanizing, which is a kind of chemical treatment for workpieces. After phosphating, a layer of film is formed on the surface of the workpieces, covering the surface unevenness created by acid pickling, making the pickled surface smoother and more conducive to hot-dip galvanizing.

In summary, the acid pickling process is a necessary step for hot-dip galvanizing process to ensure proper adhesion and corrosion resistance of the coating.We should strictly control the concentration and temperature of the acid to avoid causing unnecessary damages to the workpieces.