The authoritative public forum
  for Metal Finishing 1989-2025
  

  -----

Olive drag passivation

2005

I am looking for the make-up of an olive drab passivation solution. Yes, there are several patented solutions on the market, but, somewhere somebody must have one of the old reliable make-up methods.

My application is for ammunition boxes (we manufacture the hinges, zinc plate, olive drab passivate, cure and then send for KG Gunkote). The curing temperature (150 °C) is my major concern due to the fact that passivated surfaces should not be subjected to temperatures above 60 °C.

A lot of work still lies ahead before our process can be "qualified", and the more methods we have to experiment with the better.

Tommy van Rensburg
fasteners for various industries - Alberton North, Gauteng, South Africa

---

2005

Tommy

Stay with the Patented solutions and focus more on drying below 70 °C which is right for OD passivate.

If perhaps you need to Hydrogen De Embrittle, ensure the parts are passivated after the de embrittlement process.

At 150 °C most Passivated films lose their color and de hydrate.

There is one Trivalent Chromate that does accept 180 °C and it is proprietary in nature and should be available in your country. The color of the finish is light green but I can't name the maker as this is not permitted here.

Regards,

Asif Nurie [deceased]
- New Delhi, India
With deep regret we sadly advise that Asif passed away on Jan 24, 2016