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The cathode efficiency depends on the process and varies between 90 and 97%. Due to this mismatch, during the plating the nickel concentration in the solution and the pH will slowly rise. [6] The process takes minutes to hours depending on the current density and the intended thickness of the plating. [7]
It is filled with a sample of the plating solution and an appropriate anode which is connected to a rectifier. The "work" is replaced with a Hull cell test panel that will be plated to show the "health" of the bath. The Hull cell is a trapezoidal container that holds 267 milliliters of a plating bath solution.
The main ingredients of an electroless nickel plating bath are source of nickel cations Ni 2+, usually nickel sulfate and a suitable reducing agent, such as hypophosphite H 2 PO − 2 or borohydride BH − 4. [1] With hypophosphite, the main reaction that produces the nickel plating yields orthophosphite H 2 PO − 3, elemental phosphorus ...
A sulfate-based bath that uses insoluble catalytic anodes, which maintains an electrode potential that prevents oxidation. The trivalent chromium-plating process can plate the workpieces at a similar temperature, rate and hardness, as compared to hexavalent chromium. Plating thickness ranges from 5 to 50 μin (0.13 to 1.27 μm). [2]
Thick coatings require more process control, [6] and are produced in a refrigerated tank near the freezing point of water with higher voltages than the thinner coatings. Hard anodizing can be made between 13 and 150 μm (0.0005" to 0.006") thick.
High zinc improves the bath's efficiency (plating speed), while lower levels improve the bath's ability to throw into low current densities. Typically, the Zn metal level varies between 20 and 50 g/L (2.7-6.7 oz/gal). The pH varies between 4.8 and 5.8 units. The following chart illustrates a typical all potassium chloride bath composition:
Copper plating on aluminium. Copper electroplating is the process of electroplating a layer of copper onto the surface of a metal object. Copper is used both as a standalone coating and as an undercoat onto which other metals are subsequently plated. [1]
Electroless nickel immersion gold (ENIG or ENi/IAu), also known as immersion gold (Au), chemical Ni/Au or soft gold, is a metal plating process used in the manufacture of printed circuit boards (PCBs), to avoid oxidation and improve the solderability of copper contacts and plated through-holes.