Nickel-alloy container

A similar method of test was used at the International Nickel Company s Corrosion Laboratory at North Carolina. The specimen discs are mounted on insulated vertical spindles and submerged in sea-water, which is supplied continuously to the tank in which the specimens are immersed. The maximum peripheral speed of the spinning disc is about 760cms , and the characteristic pattern of attack is shown in Fig. 19.3a. Studies of variation of depth of attack with velocity indicate that at low velocities (up to about 450 cm s ) alloys such as Admiralty brass, Cu-lONi and cupro-nickel alloys containing iron maintain their protective film with a consequent small and similar depth of attack for the diflferent alloys. At higher velocities the rate increases due to breakdown of the film. 

Nickel alloys containing from about 1 to 2 wt. % Cu were less active than nickel itself (at — 78°C and at room temperature as well), and the... 

ASTM A 494/A 494M-04 Standard Specification for Castings, Nickel and Nickel Alloy (contains many of the corrosion nickel alloy castings)... 

Heating moist Raney nickel alloy containing 20% aluminium in an autoclave under hydrogen caused the aluminium and water to interact explosively, generating 1 k bar pressure of hydrogen. 

Hydrogen absorption/desorption characteristics of magnesium-nickel alloy containing 23 atomic% Ni. (Reproduced with permission from Schwarz, R.B., Storage of hydrogen in powders with nanosized crystalline domains, Mater. Res. Bull., 24, 40, 1999, available at http //www.wtec.org/loyola/nano/US.Review/04 06.htm, May 2007.)... 

Aluminum bronzes, copper-nickel alloy (69 Cu-30 Ni-1 Fe and copper-nickel alloys containing added manganese are resistant to impingement and cavitation-induced damage under flowing conditions. 

The two main nickel alloys containing about 99% nickel with remaining 1 % consisting of Cu, Fe, Mn, Si, C and S are known under the designation of alloys 200 and 201. The composition of these alloys is given in Table 4.33. 

Nickel alloys containing chromium and iron of the composition given in Table 4.38 are used widely in chemical, petrochemical and other high-temperature processes. 

Cobalt is present in almost all nickel ores. Previously there was no use for cobalt and as its value was less than that of nickel, it was not separated. Therefore, old nickel alloys contain much more cobalt than those of the present day. Two chemical methods are based on the oxidation of cobalt to three-valent ions. Cobalt is precipitated as cobalt(III) hydroxide by treating the solution with chlorine to oxidize the cobalt(II) to cobalt(III) and adding nickel carbonate to control the pH to 4 (27)... 

Invar. TM for an iron-nickel alloy containing 40-50% nickel and characterized by an extremely low coefficient of thermal expansion. 

Stabilizing is done on certain corrosion resistant stainless steels and nickel alloys containing titanium, niobium or tantalum to enhance corrosion resistance. They are heated to specific temperatures so that these elements combine preferentially with carbon, preventing any detrimental loss of... 

Monel 400, a nickel alloy containing 66.5% nickel, 31.5% copper and 1.25% iron, has a marked tendency for the initiation of pitting in chloride-containing environments where the passive film can be disturbed. Under stagnant conditions chlorides penetrate the passive film at weak points and cause pitting attack. Sulfides can cause either a modification of the oxide layer, as described for copper, or breakdown of the oxide film of nickel alloys. Pit initiation and propagation depend on depth of exposure, temperature and presence of surface deposits. Little and coworkers [30] reported selective dealloying of nickel in Monel 400 in the presence of SRB from an estuarine environment. 

Smelting to ferronickel is essentially the same as matte smelting, except that no sulfur is added. It is often applied to laterite ores. The resulting iron-nickel alloy contains 20-50% nickel [46]. 

Monel 400 is a nickel alloy containing 30-33% copper. The corrosion of Monel 400 is negligible in all types of atmospheres. When exposed to rain, a thin gray-green patina develops. In a sulfurous atmosphere a smooth, brown adherent film forms. Because of its low corrosion rate and the pleasing patina that forms. Monel 400 is used for architectural applications such as roofs, gutters, and flashings. 

The sensitivity of the test is shown by the fact that a positive response was obtained with a manganese bronze containing 58.8 % Cu, 33.9 % Zn, 1 % Mn, 0.9 % Fe, and 1.62 % Al. In contrast, a manganese-free bronze showed no reaction but a positive response was obtained with a copper-nickel alloy containing 0.98 % manganese. 

In high nickel alloys containing molybdenum, such as 15% Cr, 15% Mo, 4% W, 5% Fe, 0.06% C and balance Ni, intergranular attack is generally attributed to the depletion of molybdenum and chromium, because of the formation of M C (molybdenum carbides and chromium carbides (M23C6). 

PH (Precipitation hardening). These are iron-chromium-nickel alloys containing precipitating element, such as Al. Strength is achieved by precipitation hardening heat treatment. One example is (17-7 PH)... 

---