Tin and Tin-Alloy Plating
shiny and bright
Schlötter developed the world’s first bright tin plating formula, which is now widely used in many tin plating factories around the world. Schlötter has developed highly modern processes for tin plating and its alloys. These include bright tin, matte tin, tin-lead, tin-bismuth, and tin-silver processes.
Bright tin plating process SLOTOTIN 70
This process is based on sulfuric acid and creates a bright tin coating in barrel and rack plating. The bright tin coating is applied at very low current densities, making it ideal for plating complex-shaped parts.
Matte tin plating process SAT 30-1
The matte tin plating process SAT 30-1 is based on sulfuric acid and produces a fine-grained coating with excellent throwing power and high solderability. This process is used in the plating of electronic and electro-technical components.
Its application is primarily limited to the PCB industry because the resistance of the coating produced by the SAT 30-1 matte tin plating process must be tested before use. This process is used in both rack and barrel applications. The coating created by this process maintains excellent solderability even after heat treatment at 155°C for 16 hours.
The formation of quaternary lead compounds reduces the cloudiness of the solution. The SAT 30-1 matte tin plating process is a straightforward process in terms of application and maintenance.
The concentration of the binary lead and sulfuric acid must be controlled by analysis, and the depletion of additives, mainly due to drag-out, must be replenished periodically.
The additives used do not include alkyl phenol ethoxylates (nonyl phenol ethoxylates).
Lead-tin alloy plating process LA
The matte lead-tin alloy plating process LA is primarily used to create lead-tin coatings on printed circuit boards (PCBs). However, it is also used for plating other electronic components. This bath is based on fluoboric acid and creates a very fine crystalline coating with approximately 60% lead in the alloy, which may vary depending on the bath composition.
Lead-tin alloy plating process SLOTOLET K
The SLOTOLET K lead-tin alloy plating process is a strong acid electrolyte that is fluoride-free, specifically designed for plating printed circuit boards (PCBs) and other electronic components. This electrolyte produces coatings with a good crystalline structure (fine-grained) without dendritic formation.
The amount of lead in the alloy coating ranges from 95% to 5%. In the PCB industry, coatings with approximately 63% lead content are preferred. However, in this process, a coating with approximately 70% lead content is preferred. The lead content for final coatings ranges between 85% and 80%.
High-speed reel-to-reel plating – MBF 20
For high-speed reel-to-reel plating of both bright and matte lead, Ashlor offers a variety of processes that are highly suitable for plating on copper wires, aluminum, or brass sheets. This process is used in continuous plating lines with high quality and speed.
Lead-free anti-tarnish coating:
To prevent darkening and matting of tin coatings after plating, an anti-tarnish process is used, which helps maintain the solderability, durability, and color stability of the tin coating without affecting its solderability.
It is worth mentioning that various plating solutions are available for lead-tin alloys, lead-copper, lead-bismuth, lead-silver, lead-nickel, and lead-zinc alloys.