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Old 10-05-2012, 08:31   #15
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Location: Rhode Island
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Originally Posted by ricklee4570 View Post
If they both are so similar and both have the same byproduct of cyanide, why did Glock switch?
At this time, I'm not convinced that they have. However, that said, both the Melonite and Tenifer processes develop small amounts of cyanide and cyanate in the nitriding salt bath as the process is performed. The cyanide and cyanate are important to the reactions that take place in the salt bath as the medium interacts with the surfaces of the ferritic materials being processed. The compound layer of nitride is formed, and a diffusion zone made up of carbon and nitrogen components is immediately beneath. Once the process cycle is completed, the parts are removed from the nitride bath and immersed in a second oxidizing salt bath that chemically destroys the cyanide and cyanate. Subsequent to immersion in the oxidizing bath, the parts are removed and cooled in water to near room temperature, followed by washing to remove salt residues.

With proper immersion of the parts in the oxidizing bath, cyanide and cyanate by-products are destroyed. Analyzing the wash water will reveal that free cyanide is not present. If both processes are performed correctly, Glock should not have significant concerns with cyanide being present on the parts they surface treat after they are FNC processed.

My direct familiarity with the salt bath FNC processes noted is limited to the Melonite, as we perform said process in our company, which is involved in commercial heat treating.

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