Calculation of recovery plasticity in multistage hot forging under isothermal conditions

Abstract

A widely used method for hot forming steels and alloys, especially heavy forging, is the process of multistage forging with pauses between stages. The well-known effect which accompanies multistage hot forging is metal plasticity recovery in comparison with monotonic deformation. A method which takes into consideration the recovery of plasticity in pauses between hot deformations of a billet under isothermal conditions is proposed. This method allows the prediction of billet forming limits as a function of deformation during the forging stage and the duration of the pause between the stages. This method takes into account the duration of pauses between deformations and the magnitude of subdivided deformations. A hot isothermal upsetting process with pauses was calculated by the proposed method. Results of the calculations have been confirmed with experimental data.

Evaluation of metal plasticity and research on the mechanics of pressure treatment processes under complex loading

“…In the experimental tests, a flare at the flange equator arises with a flange diameter of d max =48 mm for a value of r/d 0 =0.25 (r=4.26 mm). The results of the calculations coincide satisfactorily with the results obtained in [1][2][3][4]23].…”

“…Workpieces of the desired accuracy in shape and size can be obtained in one transition or, due to the plasticity resource depletion, in several transitions associated with intermediate annealing to restore the plasticity of the workpiece material. In the second case, non-monotonic processes of plastic shaping can be used with high efficiency, which is also connected with the formulation and solution of new problems in the theory of plasticity [1][2][3][4].…”

Theoretical and Experimental Substantiation of the Extraction Process With Thinning Bimetallic Tubular Elements of Dissimilar Metals and Alloys

“…The sharp competition of mechanical engineering products in the world market requires the mobility of production, and discrete unstable programs of production of productsproduction of their single copies. The mobility of production can be provided by using the universal equipment of machinebuilding enterprises, as well as by creating technologies for the manufacture of bimetallic tubular elements from traditional semi-finished products, such as sheet semi-finished metals and alloys, using non-complex die tooling methods of extraction [7,14,20].…”

Numerical simulation of cold forging process to investigate folding defect in enclosed dies

“…In this process, the cylindrical solid or tubular billet is located in the die cavity and is squeezed by multiple rams. The billet is compressed with one or two opposite rams movement and the billet material fills the die cavity [1][2][3][4][5][6][7][8][9][10][11][12][13][14].…”