Out of the Ni-base-alloy spectrum for marine applications Ni-Cr-No alloys present the highest resistance against local and uniform corrosion.
One alloy of this family is alloy 59, developed in the late 1980s and has been in the market for over 10 years. Due to its nominal chemical composition of 59 % nickel, 23 % chromium, 16 % molybdenum
and an iron content below 1%, alloy 59 has excellent corrosion resistance, evidenced by its high PRE (Pitting Resistance Equivalent) number and confirmed in various investigations and field studies.
The absence of W and Cu in alloy 59 accounts for its high thermal stability. Together with its low sensitivity to hot cracking, alloy 59 shows very good weldability, verified for all technical welding processes by the German TUV and the American Bureau of Shipping. Corrosion test results obtained in lab trials in standard test solutions and in natural seawater show that the resistance to pitting corrosion, crevice corrosion and uniform corrosion of joint and overlay weldments is comparable to the behaviour of the base material. This paper presents an overview of the corrosion resistance and potential applications of alloy 59
as a filler metal for marine industries.
Key words: Alloy 59 UNS N06059, filler metal, nickel alloy, marine, offshore, localized corrosion,uniform corrosion