mechanism of cell ageing and cell death are described in this presentation.Full description
Operating Instructions for the Jiggle Cell
Overview:
The Jiggle cell is an especially useful test device for controlling and/or trouble-shooting all types types of electrolytic nickel plating solutions. It is is also also uniquely well suited suited for comparing the relative performance characteristics of different addition agent systems. Perhaps the major advantage of the Jiggle cell is that it uses a bent cathode test panel, rather than a flat panel. The obvious benefit of this configuration configuration is that it creates shelf areas and recesses that correlate much more closely with the situations platers actually encounter in production. Another benefit is that the Jiggle cell utilizes a convenient solution volume of 1000 ml. Thus, computing additions is straight-forward: a 1 ml. addition to the Jiggle cell is equivalent to adding 1 gallon of material to a 1000 gallon production tank. Similarly, adding 7.5 grams of a powder is equivalent to adding 1 oz/gal to the main solution. solution. The larger cell volume also allows for more testing to be done on a single sample of solution without significantly changing operating conditions such as bath pH and addition agent concentrations. The Jiggle cell can be used with just mechanical agitation, just air agitation, or a combination of both types.
Equipment Required:
1000 ml Jiggle cell 0-10 amp Lab Rectifier Aquarium Size Air Agitator (for Air Agitated Plating Baths) Electrolytic Nickel Anode -- 1.5" x 8" Polypropylene Anode Bag 180 Grit Waterproof Silicon Carbide Sandpaper (such as 3M #9047) Zinc Coated Steel Jiggle Cell Panels Polished Brass Jiggle Cell Panels
Test Procedure:
1.
Pour 1,000 ml. of solution to be tested into Jiggle cell.
2.
Plug in heater and agitation motor (and air source, if air agitation is to be used), and allow solution to reach normal operating temperature used in production.
3.
Attach red lead from rectifier to the anode, and the black lead from the rectifier to the cathode holder.
4.
If leveling is to be measured, scratch test panel (without removing protective zinc coating) over entire surface that will face the anode in the cell. Use sufficient pressure to ensure that the scratches are through the zinc coating and into the ba se metal. If leveling is of no concern, or if tests must be run over a polished surface, omit this step.
5.
Bend test panel to approximately duplicate configuration shown in Figure 1.
6.
Remove protective zinc coating by immersing panel in a 30-50% vol. Hydrochloric Acid solution. Be sure all zinc is removed; otherwise it will create erroneous test results.
7.
Wipe panel with a small wet sponge to remove any smut on the surface of the cathode. Pay particular attention to the recessed areas, since residual smut in these areas will lead to erroneous results. Rinse well.
8.
Attach cleaned cathode to cathode holder and submerge in solution.
9.
Turn on rectifier and immediately adjust to proper amperage. Typically, a current of 3.5 amps will provide the most meaningful results. If production conditions are atypical, i.e., significantly higher or lower than normal current densities are used, select an amperage that corresponds to actual plant conditions.
10.
Plate panel for ten minutes, adjusting current as needed to maintain the initial preferred amperage during this time period. Normally the current will increase slightly from the initial setting once the cathode surface is completely coated with nickel.
11.
Turn off rectifier at the end of the plating cycle, and remove panel.
12.
Rinse panel in fresh running water, and dry.
13.
Examine panel for overall appearance and changes from previous panel(s).
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14.
Label panel listing any additions made or changes in operating conditions compared to last panel run. This will facilitate selecting the optimum additions to be made in production.
Area #1
Intermediate current density area (35-40 ASF). Demonstrates leveling with moderate thicknesses of nickel.
Area #2
Low current density area (5-20 ASF). Shows leveling with thin nickel deposits. Bottom shelf area also useful for determining the presence of suspended solids.
Area #3
1
Very low current density area (<5 ASF). Shows presence of metallic and organic impurities as well as low current density brightness and leveling characteristics. Effects of excess secondary brightener are most evident in this area.
4
2 Area #4
Extreme low current density area (<2 ASF). Shows same effects as Area #3, but at even lower current densities.
3 2
4 Area #5
High current density area (50-70 ASF). Demonstrates leveling with heavier nickel deposits.
