STEP Test Analysis of Nickel Layers
(Simultaneous Nickel Thickness and Electrical Potential Test)
The STEP Test measures the electrical potential difference between each nickel layer and the nickel thickness of each layer. The proper sulfur composition of each nickel layer can be determined by the height of the layer on the chart. The lower the sulfur content, the higher the line and the higher the sulfur content, the lower the line. This is an important test utilized to maintain the correct electrical potential difference between each layer and the proper performance of each layer. The length of the line in each layer gives the nickel thickness of that layer. The total nickel thickness is the length of the entire line. The graph below shows an example of a typical STEP Test.
STEP Test Analysis of Nickel Layers
Nickel Layer Requirements for Typical Outdoor Applications
Please note: for Nickel Thickness 1.0 mil = 0.001”
Layer |
Required mV Difference |
Thickness (mils) |
% to Total Thickness |
Sulfur Content |
Dur-Ni (Particle Ni) |
10-20 mV ˃ Bright Ni |
0.05 |
Add to Bright Ni |
˂ 0.040% |
Bright |
Reference Layer |
0.30 |
˂40% |
˃0.040% |
Tri-Ni (High Sulfur) |
20-40 mV ˂ Bright Ni |
0.05 |
Add to Bright Ni |
˃0.150% |
Semi-Bright |
100-130 mV ˃ Bright Ni |
0.90 |
≥60% |
˂0.005% |
Total Nickel |
NA |
1.30 |
100% |
|