Monel alloy

The corrosion of Monel is negligible in all types of atmospheres. When exposed to rain, a thin gray-green patina forms. In sulfurous atmospheres, a smooth brown adherent film forms. 

---

Monel alloy Monel alloy 400 Monel alloy K-500 Monell Center Monellin [9062-83-3] Monensin... 

Nickel—Copper. In the soHd state, nickel and copper form a continuous soHd solution. The nickel-rich, nickel—copper alloys are characterized by a good compromise of strength and ductihty and are resistant to corrosion and stress corrosion ia many environments, ia particular water and seawater, nonoxidizing acids, neutral and alkaline salts, and alkaUes. These alloys are weldable and are characterized by elevated and high temperature mechanical properties for certain appHcations. The copper content ia these alloys also easure improved thermal coaductivity for heat exchange. MONEL alloy 400 is a typical nickel-rich, nickel—copper alloy ia which the nickel content is ca 66 wt %. MONEL alloy K-500 is essentially alloy 400 with small additions of aluminum and titanium. Aging of alloy K-500 results in very fine y -precipitates and increased strength (see also Copper alloys). 

Aeration Control of aeration is more difficult. Aeration here means the amount of oxygen supplied either as such or, more commonly, in air. In some situations, it may not require a large amount of air bubbled through a solution to accommodate even a modest rate of corrosion of a small test-piece. Figure 19.2 shows the relationship between the rate of supply of air used for aeration and the rate of corrosion of Monel alloy in 5% sulphuric acid. 

Fig. 19.2 Effecl of rate of supply of air used for aeration on corrosion of Monel alloy in 5%...

Figure 5 is a section looking down through a fluorine cell perhaps 20 cm below the electrolyte level before any charge has passed. A Monel alloy screen (electrically floating) separates the fluorine from hydrogen. 

Figure 11 is a sketch of the face of one of our laboratory cells.4 The cell body is made of a Monel alloy and is about 60 cm tall. The cell is fed HF and electricity and fluorine and hydrogen are taken out. 

Figure 124 shows some details of the cell interior. The skirt is a solid Monel alloy sleeve extending about 2 cm below the electrolyte. (Teflon and Kel-F fluoropolymers could not be used as skirts for extended periods because they react with fluorine at the temperatures used they could probably be used as screens, however.) The screen (not shown) is an extension of the skirt. It consists of a Monel alloy sleeve with numerous 1-mm holes. The skirt and screen float electrically. They are bipolar and... 

Figure 134 is a sketch of some of the details around the anode. The carbon piece is 35 cm long and 3.5 cm in diameter. The metal hanger to the carbon connection shown was made with a nickel split sleeve with commercial galvanized steel banding clamps. (Nickel and Monel alloy banding clamps did not work well they stretched.) This mode of connec-... 

Moment of inertia, exponents of dimensions in absolute, gravitational, and engineering systems, 8 584t Momentum balance equation, 21 347-348 Momentum equation, 11 738, 739-743 Momentum flowmeters, 11 671 Monactin, chelating agent, 5 710 Monazite, 5 671 14 636 24 756-757 digestion of, 14 638 processing, 5 673 Monel, 14 14 Monel alloy, 9 595 Monel alloy 400, 17 100 Monel cathodes, 11 837 Monensin, 20 132, 133, 135, 136, 137, 139 Monensin A, 20 120... 

Tien and Howson 1981 Winhdolz 1983. Names refer to alloys of nickel. Generally there is a series of alloys with the same trade name (e.g.. Monel alloy K-400, Monel alloy K-500). 

Monel alloy Monel alloy 400 Monel alloy K-500... 

The cathodes and cell are usually made of Monel alloys or steel, the anodes of degraphitized carbon. The cathodic and anodic compartments are not separated by a diaphragm, but by steel skirts suspended from the lid into the melt. Fig. 1.7-1 shows a cross-section through an industrial fluorine cell. 

Body carbon steel, stainless steel, Hastelloy, Monel, Alloy 20, other alloys... 

Nickel-copper alloys are generally known as Monel alloys the most popular Monel alloy is alloy 400. Because copper is a more noble metal than nickel, addition of copper to nickel increase the nobility of the alloy compared with pure nickel (Friend, 1980). As a consequence, nickel-copper alloys such as alloy 400 have a lower rate of... 

Monel alloy 405 is a higher sulfur grade in which the sulfur content is increased over that of alloy 400 to improve machinability. Refer to Table 15.3 for the chemical composition. The corrosion resistance of this alloy is essentially the same as alloy 400. 

Monel alloy K-500 is an age-hardenable alloy that combines the excellent corrosion resistance characteristics of alloy 400 with the added advantage of increased strength and hardness. Qiemical composition will be found in Table 15.3. 

Hydrofluoric acid, hydrogen fluoride and fluorine are less corrosive to many metals and alloys than their own halide counterpart. The nickel-copper alloys, typified by Monel alloy 400 have excellent resistance to hydrofluoric acid corrosion. Stainless steels, such as 316, suffered severe transgranular corrosion. Table 9.23 summarizes the corrosion resistance of nickel alloys and stainless steels in anhydrous hydrogen fluoride [37]. The weakness of stainless steel to anhydrous hydrogen fluoride corrosion is shown in Table 9.23. 

These alloys are well-known for their excellent corrosion resistance to seawater. They have been used as propellers, pump shafts, impellers and condenser tube materials. The best known is Monel (Alloy 400). It is resistant to brine and immune to stress corrosion cracking and pitting in chloride and caustic alkaline solutions. It is also resistant to HF and fluorine containing media. 

Monel alloy R-405 has specified amounts of sulfur for improved machining characteristics. Monel K 500 has the dual advantage of improved mechanical strength and excellent corrosion resistance. It can retain strength up to 650 C and ductility up to 134°C. 

---