The authoritative public forum
  for Metal Finishing since 1989
  

  -----

Methods of measuring etch depth

2003

Dear sir,

We're trying to etch and passivate SS 316 LN using sulfuric acid and phosphoric acid mixture. Is it possible to find out the thickness of the material (in microns) removed by any means other than by weight loss method.

Thank you,

R. Sudha
student - Chennai, Tamilnadu, India

---

Hi,

You could use laser scanning electron microscopy to locate depth or volume of etched area and then calculate over the entire specimen, of course this could be time consuming, to shorten it you could use statistics to average the no and volume of etched areas. A better option would be to determine the amount of material leeched into the solution by use of spectrometry, but that may not tell the thickness of the material lost but just the amount.

Anup Holla
- Karnataka, India
2003