Different methods are considered for compacting materials, including "green" graphite billets. It is shown that the majority of these methods, in particular compaction of powder mixes, are used for this class of powder bodies. A considerable future is noted for the use of hydrostatic pressing in order to prepare fine-grained isotropic graphites that are used most widely in the national economy, in particular in the production of electronic technology. The main pioneers in Russia for preparation of isotropic graphite, prepared by hydrostatic pressing, are shown.Compaction is a process of changing the shape and dimensions of an original mass due to reducing the volume with action of external forces, and also giving a billet a specific strength required for retaining it shape during subsequent production treatment. Methods for compacting billets are very varied [1,2]. With respect to the time of action they may be separated into continuous and interrupted. According to the principle of pressure application they may be separated into gradually increasing, instantaneously increasing, and vibration, according to the scheme of increasing load they may be separated into unidirectional, two-directional, all-round and centrifugal, according to applied temperature they may be separated into cold compaction at room temperature (surrounding temperature) and hot, i.e. at elevated temperature, with respect to atmosphere they may be separated into compaction in air, in a vacuum and in an inert medium. Each of these compaction methods has its own features. We consider each method briefly.The continuous method relates to the majority of compaction cases when there is piecewise preparation of billets: compaction by a different class of presses (hydraulic, mechanical, vibration), and also different forms of isostatic (all-round) compaction: hydrostatic in thin shells, isostatic in thin-walled elastic shells, hot isotatic, and explosive.The discontinuous method, by means of which it is possible to obtain billets of significant length, relates to: compaction by extrusion, wedge compaction, rolling of powders, and also the new method of continuous compaction of billets from a hot coke-pitch mix with continuous extrusion of individual portions of material into the main formable mix.In order to prepare carbon-graphite materials the most widespread methods used are compaction in a die and extrusion (nozzle compaction). Comparative evaluation of compaction by extrusion points to the following advantages: the possibility of preparing billets of uniform density with a high ratio of length to cross sectional area, high productivity and economy of the method. The first advantage is achieved by uniform compaction of material by forces that arise in overcoming resistance caused by the walls of the nozzle, and the possibility of continuous occurrence of extrusion. Absence of damage at the nozzle surface, having a friction coefficient for the mix over the nozzle walls, and also with an unchanged compaction rate the extrusion resistance should be k...

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An effective method is demonstrated for improving the quality of carbon materials and graphite, whose articles are used extensively in different branches of the national economy. This method with use of the "nudel process" includes preparation of a strong and compact filler. The low temperature for filler preparation (550°C) provides a synchronous nature for its shrinkage with the binder during subsequent heat treatment, which reduces to a minimum structural defects for the final material, and as a consequence, it considerably increases the physicomechanical and operating properties similar to the properties of normal high quality materials, and the level of quality for the latter is achieved by repeated production cycles of impregnation of coal tar medium-temperature pitch, i.e. firing. The operational properties of articles made from the material exceeds the similar properties of articles made from traditional materials. The marked production advantages of the suggested version for carbon material using the nudel process are a significant reduction in the time of graphite preparation, a reduction of discharge into the atmosphere of cancerous substances (pitch vapors) and carbon dust; reduced gas flow rate, electric power, spilled materials, and other material expenditures.In various branches of the national economy there is extensive use of carbon materials and articles made from them: fired and self-firing anodes for aluminum electrolyzers, electrodes of ore heating and steel pouring furnaces, crucibles for melting various metals and alloys, furnace heaters for different purposes, etc. Production of carbon materials, for example graphite grade GMZ, is accomplished by a production scheme illustrated in Fig. 1. an increase in their density and strength is achieved as a result of using additional production operations of impregnation with medium-temperature coal tar pitch followed by firing. However, use of additional operations markedly increases the duration of production of carbon materials and graphites, and also their cost, but it avoids considerable nonuniformity of billet properties. This leads to a delay in the development of new fields of contemporary engineering.In order to create new carbon materials, in particular self-firing anodes for aluminum electrolyzers with increased uniformity and operating stability, we have used experience accumulated in developing articles for special technology and other forms of articles made from structural graphite. On the basis of previous experience new specifications have been formulated for the filler: to have a uniform macrostructure with low defectiveness (porosity, cracking); to exhibit high adhesion to the binder; to have the optimum structure depending preparation temperature; to exhibit a good capacity to graphitize (with a requirement of performing a material graphitizing operation).Proceeding from these requirements for preparing a strong anode or graphite with increased operating stability, it

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