Vlasov A.V., Shitikov. A.A., Maystrov Yu.V., Alimov A.A.

Strain hardening of steel 08Ю by the results of experiments on shear and longitudinal compression

The results of the experimental determination of the curves of work hardening of sheet metal with nominal thickness 0.86 and 3 mm from steel 08JU are shown under deformations exceeding the true deformation in the experiments on the uniaxial tension, using testing longitudinal compression and shear. Hardening curves can be used as input data for mathematical modeling of stress-strain state of parts during forming.
Keywords: tests of sheet metal materials; compression testing; shear testing; methods; cold deformation; the curve of hardening.

Chumadin A.S.

Theoretical methods of calculating of forming limit in sheet metal processing

A review of theoretical research on the limiting deformation of thin-walled semifinished products in various processes of sheet metal forming
Keywords: sheet-metal stamping; limiting deformation; theory.

Karpov B.V., Skripalenko M.N., Skripalenko M.M., Tran Ba Huy, Gladkov Y.A., Gartwig A.A.

Modeling of the flow-through flaw formation during three-high helical rolling on mini-mills

The experimental rolling processes are aimed to study of flow-through flaw formation and its possible minimization and have been conducted for workpieces made of titanium alloy BT-6 with different cone angles at the end face plane. The experiments have been performed on three-high mini helical rolling mills of the Department of Metal Forming of the National University of Science and Technology MISiS. The experimental rolling processes were simulated using computational QForm software for finite element analysis. The experimental and simulation results were implemented for carrying out of full 23 factorial experiment and obtain the regression equation for calculation of flow-through flaw depth depending on the initial diameter of the workpiece, final rod diameter and half cone angle of the end face plane of the workpiece.
Keywords: helical rolling; three-high rolling mill; computer simulation; flow-through flaw; regression equation; full factorial experiment.

Zhelezkov O.S.

Prospects of rotary and rotary-conveyor lines using in the production of fasteners

Currently, mass production of fasteners is carried out with the use of automatic forging machines of intermittent operation, which, after reaching maximum speed of 500…600 strokes per minute, almost exhausted the reserves of the further increase in performance. Significant performance improvement of the fasteners manufacturing processes is possible by means of creation and implementation of rotary and rotary-conveyor lines.
Keywords: fasteners; automatic forging machines; automatic rotary and rotary-conveyor lines; bolts; nuts; screws; rivets; rotary technology.

Krivitsky B.A.

Evaluation of the thermal effect during high-temperature torsion testing of superalloy ХН56ВМКЮ

The methodology and the results of an experimental study of the thermal effect during high temperature torsion test of heat-resisting alloys specimens are presented. A significant warming under certain loading conditions was found. It is affects on hardening curve construction and mathematical simulation of metal forming processes database software formation. Otherwise, a significant mistake in results of thermal fields and power parameters calculation is introduced. Based on the findings, recommendation of testing methodology improvement and hardening curve construction are presented.
Keywords: torsion testing; strain heating; mathematical modeling; processing pressure.

Zheleznyak L.M., Bekmansurov R.R.

Features of production of collector strips – responsible products of non-ferrous metals industry

The choice of alloy for manufacturing of collector profiles is difficult task, as it needs to have a high level of service properties. Cadmium bronze brand CuCd1, despite on its environmental harm, has a number of advantages due to it is in a priority. The operating conditions of electrical machines vital purpose require much higher performance bands, therefore, on the basis of results of experimental-production studies, organized by the release profiles of this bronze, but more restrictive in relation to the standard requirements. Obtaining high parameters of the collector profile is achieved by the following processing methods: increasing the coefficient of compression in thickness in the finishing drawing pass; decreasing in camber of the bands due to the transition to the progressive method of electro-erosion cutting and pressing dies and matrices; using of nickel alloy «Nimonic» as the material forming matrices and application in all the aisles composite drawing dies with carbide inserts working. Silver bronze СuAg1 is an alternative to cadmium bronze, which doesn’t concede in service properties, but surpassing it in environmental and other indicators. Mechanical and electrical properties of the collector strips from this bronze fully meet customer requirements and standard specifications.
Keywords: electrical bronze; collector stripes; stringent regulations; process regulations; silver bronze; mechanical and electrical properties.

Polyakov P.A., Kolmykov V.L., Mushnikov A.N., Polyakov A.P., Dolmatov A.V.

Solidity of unsintering briquettes from iron-based powders

Solidity of unsintering briquettes from iron-based powders is investigated according to test results on axial and radial compressions and hardness measurements depending on the density of samples. The features of the formation of the strength properties of each of the powder compositions are shown. The conditions of the yield surface of Drucker-Prager limit parameters are defined.
Keywords: pressing; powder composite; compressive strength; hardness.