Alloying additions major

Extensive studies have been carried out by Giggins and Pettit and by Vasantasree and Hocking on a range of nickel chromium alloys with up to 50% alloying addition. Generally the principles outlined above can be used to interpret the experimental observations, where the thermodynamics of the reaction are a major factor determining the rate of attack, depending upon whether oxide or sulphide is the stable phase. 

In these doped alloys, the major phase () had the composition of the Ni Al3 phase and a small amount of dissolved Cr ( -1.5 at %) and Mo ( V 0.2 at X). This primary phase was surrounded by a small amount of a binary phase (Cr Alg) in the case of Cr addition, and of two phases in the case of Mo addition (P., = NiAl + 0.3 % Mo and a ternary phase Pg = (NiMo)Alg). The proportions of the various phases in the alloys varied and the quantity of phase Pj decreased significantly when the Mo content increased. 

To summarise the results concerning the study of reversibility of metal-support interaction states, we could first state that the classic reoxidation treatment at 773 K does not allow the recovery of the NM/Ce02 catalysts from the decorated or alloyed states. The noble metal/ceria phase separation may only be achieved upon reoxidation at temperatures well above 773 K. This observation represents an additional major difference between titania and ceria supported noble metal catalysts. Moreover, the likely regeneration of NM/CcOi catalysts reduced at 773 K by reoxidation at 773 K would actually prove, in good agreement with earlier HREM studies on the reduced catalysts (117,194), that the observed deactivation effects are not due to decoration or alloying phenomena, rather consisting of purely electronic effects (105). 

ALLOY COMPOSITION -major constituents -minor additions -impurities... 

The third group is named after the austenite phase, which for pure iron exists as a stable structure between 1670 and 2552°F (910 and 1400°C). It is the major or only phase of stainless steel at room temperature, existing as a stable or metastable structure by virtue of its austenite-forming alloy additions, notably nickel and manganese. These stainless steels have face-centered austenite structure from below 32°F (0°C) up to near melting temperatures. 

The next major step in alloying additions comes from molybdenum. This element also provides excellent corrosion resistance in oxidizing... 

The mechanical, physical, and chemical properties of aluminum alloys depend on composition and microstructure. The addition of selected elements to pure aluminum greatly enhances its properties and usefulness. Because of this, most applications for aluminum utilize alloys having one or more elemental additions. The major alloying additions used with aluminum ate copper, numganese, silicon, magnesium. 

Aluminum. The majority of aluminum containers are of monobloc (one-piece) constmction, impact extmded from a slug of lubricated aluminum alloy. These containers are widely used for many products and are available in a vast array of heights and diameters. Because these containers lend themselves to additional shaping, many unusual shapes can be found in the marketplace. They may also be coated after the extmsion process. 

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