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DISSERTATION TITLE--RESEARCH OF OF SHELLS'S DESTRUCTION IN KRISTALLIZATION MACHINES DURING CONTINUOUS CASTING OF PURVEYANCES AND RISE OF THEIR FIRMNESS

The scientific chief : a. prof. Leirih I. V.

Continuously casting has the row of advantages before other methods of receipt of metallic bars. Major in them: high performance, comparatively low unit cost thanks to the high outputs of suitable, possibility of mechanization and computer-aided manufacturing, high quality of bar, because of features of crystallization in the conditions of directed teplootvoda and possibility of management of them.
Kristallizator- major part of any machine of the continuous casting - is intended for forming of the set type of inundated in him metal or alloy. The duindexle crust" of hardening metal, able to serve by an original capacity for the crystallized fusion, appears in kristallizatore. Most casting defects, bar, beginning from the breaches of metal and ending by distortions of sizes of the set type and cracks, in a greater or less degree are related to construction of kristallizatora materials, which he is made from . Kristallizator is teploobmennik and, consequently, material which he is made from must be the hot-water system. Therefore from the beginning of application of the continuous casting the unalloyed copper served by material.
 to communication with that kristallizatori from a copper enough quickly fall out. Reasons following:
- deformation of walls in vertical and transversal directions from tensions in them is higher than limit of fluidity of copper; it is possible that this deformation is related to the change of sizes of wall under action of cyclic heat treatment as a result of the termostrukturnih tensions caused by anizotropnostyu of crystals on the coefficient of linear expansion and resilient properties;
-Wear as a result of friction of bar at the surface of kristallizatora, resulting in violation of his thermal balance.
Indicated the reasons of death copper kristallizatorov touch both shell and collaindexible kristallizatorov. All it tells on quality of the bars poured off: sharply a surface, cracks because of laboured usadki of hardening crust of bar appear, permanent breaches of metal from the unsatisfactory cooling and etc, gets worse
By such appearance, growth of speed of pouring, and also increase of sizes of the bars poured off promote the requirements to mechanical properties of material of kristallizatora and saving of these properties long we tell at the promoted temperatures (temperatures of contact of molten metal and kristallizatora), I.e. to the rise of heatproof. There was a problem touching material of kristallizatorov and rise of their firmness. Especially sharply she showed up at casting of slyabovih bars of steel on the radial machines of the continuous casting, although in a greater or less degree this problem touches casting of of high quality bars of steel, bars from a copper, copper alloys, nickel and dr.
 to the given work the reasons which destruction of copper kristallizatorov with chromic coverage in the process of work of machine of the continuous casting is result of are explored.The methods of rise of their firmness are developed.