Alloy 625 is the most popular alloy for weld overlay.
Without considering the price factor, would NiCrMo-3 be the best technical option for weld overlay of API 5L and low alloy steels, in general, for the petrochemical industry?
ERNiCrMo-3 is used primarily for welding Inconel-601 and Incoloy 800. It can be used to weld dissimilar metal combinations such as steel, stainless steel, Inconel and Incoloy alloys. However, for welding Inconel 625, ERNiCr-3 can be used.
@ Nelaturi V Raghavaiah , good morning!
Thank you for your nice support. I am starting a huge project to test different filler metals for weld overlay of carbon and low alloy steels and compare the samples with the one weld overlaid with ERNiCrMo-3. I am considering ERNiCr-3 as you suggested.
We intend to test both mechanical properties and corrosion resistance.
Hi André Vicente ,
The environment must be considered for choosing the proper corrosion resistant weld overlay alloy. There are many different environments in the petrochemical industry that lead to different damage mechanisms including chloride, hydrogen, H2S, napthenic acid, sulfuric acid, oxidizing, reducing, high temperature, low temperature, and etc. See the API RP 571, "Damage Mechanisms Affecting Fixed Equipment in the Refining Industry" for more information about corrosive environments in petrochemical processing.
Rather than using a nickel alloy like ERNiCr-3 as your comparison alloy, would actually say that, depending on the environment (for a mildly corrosive environment), a basic weld overlay would start with a stainless steel like ER308 or ER309. If the "L" designation shows up after the symbol, as in ER309L, the filler metal is a low carbon alloy, which is important for high temperature applications where sensitization might be an issue. Table 4 in this linked ASM document, "Stainless Steel and Weld Cladding Overlays starts with the most basic stainless steel overlays and works it's way down to more specialty, complex cladding alloys:
https://www.asminternational.org/documents/10192/22833166/06398G_Sample_BuyNow.pdf/152a4ca7-ca11-4a48-ad7d-4c2b2c39bd16
Attached, the "Engineering with Clad Steel" gives some helpful descriptions of environments and claddings used in Table 3. Also attached is a TWI document by Kumar et al about nickel alloy cladding (ERNiCr-3 / Nickel 625 alloy).
Best Regards,
Nathan
Yes, ERNiCrMo-3 can be considered for overlaying weak substrates, one of the factors to be considered is the formation of secondary phases or intermetallic compounds at the interface region. These phases may influence the mechanical properties as well as electrochemical behavior.
http://dx.doi.org/10.1590/s1517-707620190001.0627
Article Some studies on nickel based Inconel 625 hard overlays on AI...
https://link.springer.com/content/pdf/10.1007/s12540-019-00440-x.pdf- Badges
- Science topic
- Similar topics
- Physical Sciences
- Materials Science
- Materials
- Inorganic Materials
- Metals
- Alloys