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Melting and metal treatment

The selection of a melting fiimace is an important aspect in the setting up of a foundry process. Each furnace type has its own properties concerning feed requirements and alloying possibilities, which in turn will have repercussions on the full foundry process. On the other hand, the t5q)e of metal to be melted determines which furnace may or may not be used. The applicability of the various furnace types is given in Table 2.5. [Pg.28]


Figure 2.2 Process flow diagrams for the melting and metal treatment of cast iron [32, CAEF, 1997]... Figure 2.2 Process flow diagrams for the melting and metal treatment of cast iron [32, CAEF, 1997]...
Cast steel is normally melted in electric arc furnaces (EAF) or in coreless induction furnaces (IF). Once melted, the liquid metal can be refined (i.e. removal of carbon, silicon, sulphur and or phosphorus) and deoxidised (i.e. reduction of metallic oxides), depending on the base material and the quality requirement of the finished product. Figure 2.3 gives process flow diagrams for the melting and metal treatment of cast steel in the different furnace types. [Pg.17]

Prevention of visible and fugitive emissions during melting and metal treatment... [Pg.235]

Sodium nitrate is also used in formulations of heat-transfer salts for he at-treatment baths for alloys and metals, mbber vulcanization, and petrochemical industries. A mixture of sodium nitrate and potassium nitrate is used to capture solar energy (qv) to transform it into electrical energy. The potential of sodium nitrate in the field of solar salts depends on the commercial development of this process. Other uses of sodium nitrate include water (qv) treatment, ice melting, adhesives (qv), cleaning compounds, pyrotechnics, curing bacons and meats (see Food additives), organics nitration, certain types of pharmaceutical production, refining of some alloys, recovery of lead, and production of uranium. [Pg.197]

Ionic liquids formed by treatment of a halide salt with a Lewis acid (such as chloro-aluminate or chlorostannate melts) generally act both as solvent and as co-catalyst in transition metal catalysis. The reason for this is that the Lewis acidity or basicity, which is always present (at least latently), results in strong interactions with the catalyst complex. In many cases, the Lewis acidity of an ionic liquid is used to convert the neutral catalyst precursor into the corresponding cationic active form. The activation of Cp2TiCl2 [26] and (ligand)2NiCl2 [27] in acidic chloroaluminate melts and the activation of (PR3)2PtCl2 in chlorostannate melts [28] are examples of this land of activation (Eqs. 5.2-1, 5.2-2, and 5.2-3). [Pg.221]

So far, few of the commercially operated diffusion processes have been applied to the lower-melting-point metals. While they are being used to an increasing extent for protection of nickel, cobalt and refractory alloys, the bulk of present-day applications is still concerned with the treatment of ferrous materials. [Pg.396]

Modem refining technology uses tantalum and niobium fluoride compounds, and includes fluorination of raw material, separation and purification of tantalum and niobium by liquid-liquid extraction from such fluoride solutions. Preparation of additional products and by-products is also related to the treatment of fluoride solutions oxide production is based on the hydrolysis of tantalum and niobium fluorides into hydroxides production of potassium fluorotantalate (K - salt) requires the precipitation of fine crystals and finishing avoiding hydrolysis. Tantalum metal production is related to the chemistry of fluoride melts and is performed by sodium reduction of fluoride melts. Thus, the refining technology of tantalum and niobium involves work with tantalum and niobium fluoride compounds in solid, dissolved and molten states. [Pg.398]

Reduced need for off-gas treatment compared to competing technologies, such as plasma arc vitrification, molten salt, and metal melting technologies. [Pg.798]

The 1-fluoroquinuclidinium fluoride (NFQNF, 2) precipitates during the reaction and, after treatment with hot, dry acetone to remove quinuclidinium fluoride, is obtained as an extremely hygroscopic white solid which can be assayed iodometrically (reaction with aqueous acetonic KI occurs instantaneously at rt). l-Fluoroquinuclidinium fluoride (2) is readily soluble in water, methanol, ethanol, trifluoroacetic acid, and ethyl acetate, and reasonably so in acetonitrile, but appears to be insoluble in alkanes, arenes, chloromethanes, acetone, diethyl ether, tetrahy-drofuran, dimethylformamide and dimethyl sulfoxide. The fluoride 2 has a melting point of 126-128°C (dec.) and is less flammable than quinuclidine in air, igniting only on direct contact with a flame or after prolonged heating on a metal plate. It does not explode when struck with a hammer.73... [Pg.455]


See other pages where Melting and metal treatment is mentioned: [Pg.13]    [Pg.15]    [Pg.28]    [Pg.295]    [Pg.366]    [Pg.367]    [Pg.396]    [Pg.13]    [Pg.15]    [Pg.28]    [Pg.295]    [Pg.366]    [Pg.367]    [Pg.396]    [Pg.28]    [Pg.28]    [Pg.2912]    [Pg.146]    [Pg.252]    [Pg.228]    [Pg.559]    [Pg.169]    [Pg.330]    [Pg.516]    [Pg.312]    [Pg.336]    [Pg.763]    [Pg.195]    [Pg.381]    [Pg.170]    [Pg.52]    [Pg.415]    [Pg.400]    [Pg.682]    [Pg.330]    [Pg.216]    [Pg.223]    [Pg.601]    [Pg.848]    [Pg.1060]    [Pg.516]    [Pg.23]    [Pg.146]   


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Melting metal

Metallic melts

Process flow diagrams for the melting and metal treatment of cast iron

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