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The problem statement and boundary conditions for calculation of axial thermoelastic stresses in backups with unit collars of combined continuous casting and deformation are provided for production of three steel billets. The calculation scheme for determination of thermoelastic stresses in backups with collars in a known temperature field was stated using ANSYS software. The calculation results of thermoelastic stresses in shaped dies were performed in four sections of a backup with collars. In each section, calculation results are given for four typical lines and seven points. Values of axial thermoelastic stresses for seven typical points of each section are given for the contact surface of a backup with collars and the contact layer at a depth of 5 mm from the contact surface. The stress state of a shaped backup in the middle of depression between the middle collars was determined and the distribution regularities of axial and equivalent stresses over the thickness, length and width of a backup were established during slab compression and at idle. The calculation results of thermoelastic stresses in the top of the middle collar of a shaped backup on the contact surface and in the contact layer during slab compression and at idle are presented. Graphs of thermoelastic stress distribution along the line passing through the top of a collar are given, which show the zones of compressive and tensile thermoelastic stresses during slab compression and at idle. The character of the stress state in the base of extreme collar was determined for production of three steel billets in the unit of combined process of continuous casting and deformation. © 2021, Allerton Press, Inc.

Introducing systems capable of profound reduction in a casting and rolling module improves the product quality, on account of the intense working of large continuous-cast slabs over the whole cross section and the production of uniform fine-grain structure of the metal, and also increases the cross section of continuous- cast billet. Analysis of the formation of nonmetallic inclusions and segregation in the axial zone of the thick rolled sheet is followed by analysis of the nonuniform deformation over the slag height in the reduction of large continuous-cast slabs at the 5000 mill at OAO Magnitogorskii Metallurgicheskii Kombinat. The structure of a cyclic-deformation system for preliminary deformation of large continuous-cast slabs is described, and its capabilities are explored. Hammers for preliminary deformation of large continuous-cast slabs are considered. Experimental data are presented for the deformation of continuous-cast steel 45 and 12Kh18N10T steel billet. The structure of the continuous-cast billet is assessed in the course of reduction on the cyclic-deformation system. The basic parameters of the system for preliminary deformation of large continuous- cast slabs are determined. The capabilities of the cyclic-deformation system are outlined in terms of increase in sheet quality. On that basis, the use of the cyclic-deformation system in the continuous-casting line for preliminary reduction of large continuous-cast slabs is recommended: it permits matching of the speed of continuous-casting and cyclic-deformation processes; and ensures 45–90% reduction in a single pass so as to obtain well-worked cast structure over the whole slab cross section. When using the cyclic-deformation system in the continuous-casting line, the continuous-cast slabs are reduced by means of the heat of the cast metal, thereby greatly reducing the energy consumption in billet production. The cyclic-deformation system may be used with thick-sheet and broad-strip mills for preliminary single-pass reduction of the hot slab, with improvement in sheet quality and reduction in the number of passes in the mills. © 2017, Allerton Press, Inc.

A thermal deformation treatment (TDT) method is developed and implemented during production of industrial batches of chromium bronze bars, according to which aging is performed after intermediate billet drawing to a prefinishing diameter, then finishing drawing of an aged billet follows to a final diameter with a drawing factor of 1.10-1.25. Batches of bars treated by this method correspond entirely to all standard document specifications with respect to hardness and longitudinal curvature, and bars have the required marketable condition with smooth, defect-free, shiny surface typical for cold-drawn products. © 2013 Springer Science+Business Media New York.

When using continuous-cast billet in pipe rolling, it is expedient to roll the billet prior to broaching, so as to improve the structure and properties of the steel. To that end, a three-high screw-rolling mill for billet reduction has been installed at the TPA-80 pipe-rolling unit at OAO Sinarskii Trubnyi Zavod. Introduction of the new process was associated with increase in the rejection rate on account of indentations in the pipe. These indentations may be attributed to the depression formed at the rear of the billet in reduction and the subsequent formation of metallic semicircles on broaching; the semicircles break away and enter the deformation zone. The sources of the indentations on the rolled pipe are investigated. The broaching of the billet on a screw rolling mill is mathematically simulated. Recommendations are made with a view to reducing the surface defects on pipe produced by the TPA-80 unit with a reduction mill. © 2013 Allerton Press, Inc.

The feasibility of using the equal channel angular extrusion (ECAE) process for the breakdown of cast structures in commercial purity aluminium has been investigated. Billets of an as-cast coarse grained Al (99.7% pure) were subjected to ECAE at 500�C using a die that imparts an equivalent plastic strain of 0.67 per pass. Multiple extrusion passes were performed using two different processing routes: Route I in which the billet orientation was kept constant from pass to pass, and Route II in which the billet was rotated by 180� about its longitudinal axis from one pass to the next resulting alternately in shear in planes oriented at 120� to each other. Processing by Route I through five passes produced elongated grains showing evidence of dynamic recovery. Processing by Route II through five passes however produced largely equiaxed grains with a dynamically recovered substructure due to the intervention of static recrystallization during the reheating to extrusion temperature between passes. Both processing routes produced a dynamically recovered structure with equiaxed subgrains approximately 6?m in size. Sharp deformation textures were not obtained. The relevance of this technique to industrial processing is discussed. ? 2001 Elsevier Science B.V. All rights reserved.