Ferrous alloy

Metal alloys, by virtue of composition, are often grouped into two classes—ferrous and nonferrous. Ferrous alloys, those in which iron is the principal constituent, include steels and cast irons. These alloys and their characteristics are the first topics of discussion of this section. The nonferrous ones—all alloys that are not iron based—are treated next. 

FigMte 11.1 Classification scheme for the various ferrous alloys. 

Compositions of Four Plain Low-Carbon Steels and Three High-Strength, Low-Alloy Steels 

AISI/SAE or ASTM Number Tensile Strength [MPa (ksi)] Yield Strength [MPa (fcsi)] Ductility [%EL in 50 mm (2 in.)] Typical Applications 

Some 94% of the total world consumption of metallic materials is in the form of steels and cast irons. This is also true in the oil industries, with a figure around 98%. Therefore the primary choice in any material selection is steel or cast iron, unless they cannot provide the design requirements. 

The strength and hardness of steels vary considerably with both carbon content and type of heat treatment. Certain names, which relate to the carbon content, are used in coimection with steels  

Mild or low-carbon steels contain up to 0.3% carbon. Medium-carbon steels contain between 0.3 and 0.6% and tempered. 

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Ferrotantalum Ferro tellunum Ferrotitanium Ferrous Ferrous acetate Ferrous alloys... 

K00001-K99999 Miscellaneous steels and ferrous alloys... 

Most of ions do not interfere to the determination of P(V) or As(V). Big access of colored transition metals can be tolerated by using those metals solution as reference solution. It was already shown that high selectivity of the proposed method with respect to metal ions gave the opportunity to determine phosphoms in a number of nonferrous (brass, bronze) and ferrous alloys without preliminai y sepai ation. 

VERBA-XRF eoneeption effieieney shows itself in numeral methods analyzing ferrous alloys and powder-like materials like raw materials for eement industry, slag, eleetrolysis preeipitations in non-ferrous metallurgy. 

These, then, are the basic classes of ferrous alloys. Their compositions and uses are summarised in Table 1.1, and you will learn more about them in Chapters 11 and 12, but let us now look at the other generic alloy groups. 

ASM International 1997b Handbook No. 2 Properties and Selection Non-ferrous Alloys and Special Purpose Materials, 10th Edition. OH ASM International. 

The main use of the chromium metal so produced is in the production of non-ferrous alloys, the use of pure chromium being limited because of its low ductility at ordinary temperatures. Alternatively, the Cr203 can be dissolved in sulphuric acid to give the electrolyte used to produce the ubiquitous chromium-plating which is at once both protective and decorative. 

Important, but less extensive, uses are found in the production of non-ferrous alloys. It is a scavenger in several A1 and Cu alloys, while man-ganin is a well-known alloy (84% Cu, 12% Mn, 4% Ni) which is used in electrical instruments because the temperature coefficient of its resistivity is almost zero. A variety of other major uses have been found for Mn in the form of... 

The non-ferrous alloys include the misleadingly named nickel silver (or German silver) which contains 10-30% Ni, 55-65% Cu and the rest Zn when electroplated with silver (electroplated nickel silver) it is familiar as EPNS tableware. Monel (68% Ni, 32% Cu, traces of Mn and Fe) is used in apparatus for handling corrosive materials such as F2 cupro-nickels (up to 80% Cu) are used for silver coinage Nichrome (60% Ni, 40% Cr), which has a very small temperature coefficient of electrical resistance, and Invar, which has a very small coefficient of expansion are other well-known Ni alloys. Electroplated nickel is an ideal undercoat for electroplated chromium, and smaller amounts of nickel are used as catalysts in the hydrogenation of unsaturated vegetable oils and in storage batteries such as the Ni/Fe batteries. 

Martensitic phase transformations are discussed for the last hundred years without loss of actuality. A concise definition of these structural phase transformations has been given by G.B. Olson stating that martensite is a diffusionless, lattice distortive, shear dominant transformation by nucleation and growth . In this work we present ab initio zero temperature calculations for two model systems, FeaNi and CuZn close in concentration to the martensitic region. Iron-nickel is a typical representative of the ferrous alloys with fee bet transition whereas the copper-zink alloy undergoes a transformation from the open to close packed structure. ... 

FegNi. Frozen phonon calculations combined with the determination of the electron-phonon matrix in the framework of the theory of Varma and Weber have been carried out for the ferrous alloy. The resulting phonon dispersion for the bet phase was already presented elsewhere . As expected, no softening or anomalous curvatures have been detected. This confirms the existence of a bet ground state for FesNi. 

B causc ol llicir comxsion rcsisiance and the- I atl ihal copper alloys have heen used for many thoiisaiids of years, the copper alloys do not have the hi h-slreiigth qualities of the ferrous alloys, while their density is comparahle. The cost per bv soldering, which is not shared bv other metals that have reasonable corrosion resistance,... 

Dzhambasova, L., Mikhovskii, M. and Ivanov, D., Acoustic Study of Intergranular Corrosion in Non-ferrous Alloys , Tekh. Misul., 10, 115 (1973)... 

With stainless steels optimum resistance is dependent on aeration, and due account must be taken of this in considering operating conditions where previous experience has been with non-ferrous alloys which require an absence of oxygen for full resistance. There is therefore no need to run off the early distillate from a batch to avoid impurity during initial de-aeration. On the other hand, complete exclusion of oxygen for the benefit of non-ferrous metals in a mixed plant have very serious consequences for the stainless steel, and this must be kept in mind at the design stage. 

Cast iron is the term applied to a wide range of ferrous alloys, whose principal distinguishing feature is a carbon content in excess of l -7<7o. The relatively low melting point of these alloys compared with that of steels and their tendency to expand slightly on solidification, which make them admirably suited for the production of components by casting, result from this feature of their composition. 

The corrosion behaviour of amorphous alloys has received particular attention since the extraordinarily high corrosion resistance of amorphous iron-chromium-metalloid alloys was reported. The majority of amorphous ferrous alloys contain large amounts of metalloids. The corrosion rate of amorphous iron-metalloid alloys decreases with the addition of most second metallic elements such as titanium, zirconium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, cobalt, nickel, copper, ruthenium, rhodium, palladium, iridium and platinum . The addition of chromium is particularly effective. For instance amorphous Fe-8Cr-13P-7C alloy passivates spontaneously even in 2 N HCl at ambient temperature ". (The number denoting the concentration of an alloy element in the amorphous alloy formulae is the atomic percent unless otherwise stated.)... 

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