SILVER PLATING

Hana Tech Commercial Manufacture Joint Stock Company was established in 2016, with an initial capital of VND 9.2 billion and a workforce of 20 employees. With the strategic vision of expanding business and market presence, Hana Tech has invested in additional modern plating lines to meet customer demands and the needs of the supporting industry sector. One of our outstanding services is Silver Plating.

Why should customers choose silver plating?

➢ Silver is a white, lustrous, ductile metal, softer than copper yet harder than gold. It is easy to polish, has high reflectivity, and excellent electrical and thermal conductivity.

➢ Silver remains stable in many organic acids and alkaline solutions, is readily soluble in Nitric Acid, and does not oxidize in air.

➢ For these reasons, silver is widely used in various industries, such as plating jewelry, medals, spoons, bowls, plates, mirrors, automobile headlights, as well as machinery and chemical instruments, which are frequently silver-plated to resist corrosion in alkaline environments.

Silver plating methods at Hana Tech

Cyanide solution silver plating method

• This is the traditional silver plating method, using cyanide-based electrolytes. Cyanide silver plating solutions offer good distribution, fine crystalline deposition, and a bright silver-white finish.
  

• Cyanide plating baths require a certain amount of free cyanide to maintain stability, ensure uniform anode dissolution, and provide excellent electrical conductivity.
  

• Particularly for bright silver plating, higher cyanide concentration enhances the effectiveness of brightening agents.

Chemical silver plating method

• Chemical silver plating is the process of depositing a metal or alloy onto a solid surface through chemical reactions without the use of external current.
  

• This method typically utilizes autocatalytic reactions. It is based on redox reactions in which the reducing agent R in the plating solution facilitates the deposition of the metal M, while the deposited metal itself catalyzes the continuation of the reaction.
  

• The driving force of this process lies in the catalytic activity of the metal for the oxidation–reduction reaction, including cationic reactions: M + ne = M, and anionic reactions.
  

• Depending on the plating purpose and the component to be plated, different methods may be applied.

Notes on silver plating bath composition

There are many types of silver plating solutions in practice, complex cyanide salts are most commonly used as they yield fine, bright deposits. Potassium salts are more frequently used than sodium salts due to the following reasons:

1. The electrical conductivity of potassium-based electrolytes is superior to that of sodium-based ones.

2. Potassium cyanide solutions can withstand higher current density than sodium cyanide solutions. Stable current density positively impacts the deposit quality.

3. Cyanide concentration significantly influences the plating process. Increasing cyanide concentration reduces the dissociation of complex ions, enhances cathodic polarization, produces finer-grained deposits, improves thermal conductivity, and ensures better distribution of the plated layer.

4. Higher cyanide concentration also ensures normal anode dissolution, replenishing consumed silver ions and maintaining solution stability however, excessive increase may reduce anode polarization.

With a team of professional technicians, skilled workers, and state-of-the-art production lines imported from Taiwan, Hana Tech contributes to enhancing the quality and value of our customers’ components and products nationwide. At Hana Tech, you will be served with dedication and thoroughness under the motto: “Reasonable price, perfect quality!”