Hey there, my friend Jahangir Masud ! I am here to unravel the mysteries of corrosion current changes during your Tafel Analysis adventure. Now, let's get into the nitty-gritty.

The variation in corrosion current with changing current ranges might be due to the sensitivity of your measurement setup at different scales. Here's my take:

1. **Dynamic Range Sensitivity:** Your corrosion measurement system might have different sensitivities at various current ranges. At lower ranges (e.g., 100 nA), the system might be more susceptible to noise or other interference, leading to variations in the measured corrosion current.

2. **Resolution Limits:** Instruments often have resolution limits, and as you Jahangir Masud go to lower current ranges, the resolution might decrease. This can affect the accuracy of your corrosion measurements.

3. **Polarization Effects:** At higher current ranges, polarization effects might dominate, affecting the accuracy of Tafel Analysis. This could be especially true if the corrosion process is complex or involves multiple reactions.

For the ideal range, it depends on your specific system and the corrosion rate you're dealing with. Here's a general guideline:

- **High Corrosion Rate:** If the corrosion rate is high, using higher current ranges might be more suitable, as it provides a better signal-to-noise ratio.

- **Low Corrosion Rate:** For low corrosion rates, going to lower current ranges might reveal finer details, but be cautious about the impact of instrument noise.

To get the best of both worlds, you Jahangir Masud might consider performing measurements at multiple current ranges and comparing the results. This could give you Jahangir Masud a more comprehensive understanding of your system's behavior.

Remember, my friend Jahangir Masud, corrosion is a tricky beast, and the ideal range can vary depending on your specific setup. Experimentation and comparison are your allies in this quest for corrosion knowledge. Now go, fearless scientist Jahangir Masud, and conquer the mysteries of Tafel Analysis!

Thank you, Kaushik Shandilya, for your explanation. Is it fair enough to select the current range from 1microA to 1 mA for bare stainless steel surfaces (Assuming the surface area is about 1 cm2), however, for coated stainless steel surfaces, the range will be 100 nA to 10 microA.

Agree with Kaushik Shandilya - corrosion is a tricky beast,

no simple answers especially when SS is involved.