The high performance alloy UNS N06058 contains about 21 wt.-% chromium and at least 18.5 wt.-% molybdenum. It is the first member of the Ni-Cr-Mo alloys intentionally strengthened with nitrogen. Based in the combination of its alloying constitutes this alloy is highly resistant to oxidizing as well as to reducing corrosive media. Evidenced by the high Pitting Resistance Equivalent (PRE) number of about 86 the alloy UNS N06058 shows an outstanding resistance to localized corrosion as well. 

The objective of this paper is to outline the characteristics of alloy UNS N06058 and therefore to highlight the successful use of it in demanding corrosive applications in the process industry and other sectors. 

Main characteristics such as microstructure, mechanical properties and fabrication will be discussed. The very good weldability of alloy UNS N06058 has been verified by the German TÜV1. A matching filler metal, which is officially qualified according to AWS 5.14 (American Welding Society)2, is available. In addition, prior work shows that alloy UNS N06058 can be reliably explosion clad. Furthermore, corrosion resistance determined under laboratory conditions as well as in field studies will be presented not only for the base material but also exemplary on welded and cladded samples. Examples of applications will complete the comprehensive overview of this work. 

The alloys used as clad material for this study are members of the so-called “C-family”. It consists of Ni-Cr-Mo alloys, which are known for combining the corrosion resistance of Ni-Cr alloys in oxidizing media with corrosion resistance of Ni-Mo alloys in reducing media. As a result, these materials have proven to be extremely durable in a wide range of highly aggressive media. The development of these materials started in the 1930s with Alloy C. This alloy showed remarkable corrosion resistance in a wide spread of media, low sensitivity for pitting or crevice corrosion and virtual immunity to chloride induced stress corrosion cracking.