Hot dip tinning is a surface modification technique used to apply metallic coatings to workpieces by dipping them into a molten metal bath. This process is commonly used to prevent corrosion of substrates or improve conductivity and abrasion performance [1].
Here are some key points about the hot dip tinning process:
Process: Hot dip tinning involves immersing the workpiece into a bath of molten tin or tin alloy. The workpiece is typically pre-treated to ensure proper adhesion of the tin coating.
Coating Thickness: Hot dip tinning can provide a relatively thick coating compared to other tin plating methods. The thickness of the coating can vary depending on the specific application and requirements.
Coating Characteristics: The characteristics of the tin coating can vary depending on the specific process and parameters used. Some common characteristics include:
No tin whiskers: Hot dip tinning can help prevent the formation of tin whiskers, which are microscopic filaments that can cause electrical shorts in electronic components.
Good solderability: Tin coatings applied through hot dip tinning generally exhibit good solderability, making them suitable for soldering applications.
Corrosion resistance: The tin coating provides a protective barrier against corrosion, helping to extend the lifespan of the workpiece.
Electrical conductivity: Tin is a relatively good conductor of electricity, so the tin coating can enhance the electrical performance of the workpiece.
Surface Appearance: The surface appearance of the tin coating can vary depending on the specific process and parameters used. It can range from a dull streaked surface to a mirror-like reflective surface, depending on the desired finish.
Comparison with Electroplating: Hot dip tinning is an alternative to tin electroplating. While hot dip tinning offers a thicker coating and can be more cost-effective, electroplating provides better control over coating thickness and can offer a more uniform coating [3].