Development of Advanced Technologies for the Production of Innovative Materials with a Submicrocrystalline Structure by Methods of Severe Plastic Deformation

2021 ◽  
Vol 410 ◽  
pp. 191-196
Author(s):  
Danis Sh. Nukhov ◽  
Andrey O. Tolkushkin
Keyword(s):  
Plastic Deformation ◽  
Metal Forming ◽  
Metal Flow ◽  
Continuous Rolling ◽  
Axial Zone ◽  
Entire Cross Section ◽  
Product Size ◽  
Advanced Technologies ◽  
Innovative Materials ◽  
Rolling Method

A promising direction for the development of steel and alloy processing processes is the intensification of plastic deformation by creating zones of localization of shear strains not only in the longitudinal but also in the transverse directions of the deformed metal flow. Intensification of alternating deformations along the entire cross-section and, especially, in the axial zone of the billet by creating new deformation schemes is an effective way to increase the physical, mechanical and functional properties of the metal with the maximum approximation of the finished product size to the original billet size. The paper shows that a promising idea is the development of new technological schemes that implement severe alternating deformation in existing metal forming processes. A continuous rolling method of wide strips is proposed, which provides severe alternating deformation with minor changes in the size of the billet. Based on this method, a scheme of continuous rolling of the strip with the intensification of plastic deformation of the metal is designed. The results of computer simulation showed that the new rolling method increases the strain uniformity in height and the value of the strain degree in the plane of symmetry of the billet.

Theoretical Justification of the Longitudinal Rolling Method of the Thick Sheets by the Severe Shear Deformation

2020 ◽  
Vol 299 ◽  
pp. 617-621
Author(s):  
Danis Nukhov ◽  
Andrey O. Tolkushkin
Keyword(s):  
Plastic Deformation ◽  
Grain Size ◽  
Metal Forming ◽  
Large Strain ◽  
Metal Flow ◽  
Coarse Grained ◽  
Theoretical Justification ◽  
Longitudinal Rolling ◽  
Steel Sheets ◽  
Rolling Method

Severe plastic deformation (SPD) methods are based on obtaining materials with a grain size of about 100 nm by means of large strain. The SPD processes provide conditions for non-monotonic deformation of the billetsб due to the redistribution of metal macro-flows during shear or alternating strain. Numerous studies have proved the possibility of obtaining high total strain degree for a single SPD cycle. Traditional metal forming processes, such as rolling, implement monotonic deformation behaviorб due to one directional metal flow. In the process of longitudinal rolling, a banded coarse-grained structure with uneven distribution of properties in the volume of the processed metal is observed. The idea of ensuring the SPD in the process of longitudinal rolling of steel sheets is promising. The idea can be realized by the development of deformation tools and modes, which provide redistribution of metal macro-flows not only in the longitudinal but also in the transverse directions of the deformation zone.

Analysis and Technology in Metal Forming

1989 ◽  
Author(s):  
Shiro Kobayashi ◽  
Soo-Ik Oh ◽  
Taylan Altan
Keyword(s):  
Heat Transfer ◽  
Plastic Deformation ◽  
Flow Stress ◽  
Velocity Field ◽  
Metal Forming ◽  
Metal Flow ◽  
Die Design ◽  
Flow Forming ◽  
Part Geometry ◽  
Formed Part

The design, control, and optimization of forming processes require (1) analytical knowledge regarding metal flow, stresses, and heat transfer, as well as (2) technological information related to lubrication, heating and cooling techniques, material handling, die design and manufacture, and forming equipment. The purpose of using analysis in metal forming is to investigate the mechanics of plastic deformation processes, with the following major objectives. • Establishing the kinematic relationships (shape, velocities, strain-rates, and strains) between the undeformed part (billet, blank, or preform) and the deformed part (product); i.e., predicting metal flow during the forming operation. This objective includes the prediction of temperatures and heat transfer, since these variables greatly influence local metal-flow conditions. • Establishing the limits of formability or producibility; i.e., determining whether it is possible to perform the forming operation without causing any surface or internal defects (cracks or folds) in the deforming material. • Predicting the stresses, the forces, and the energy necessary to carry out the forming operation. This information is necessary for tool design and for selecting the appropriate equipment, with adequate force and energy capabilities, to perform the forming operation. Thus, the mechanics of deformation provides the means for determining how the metal flows, how the desired geometry can be obtained by plastic deformation, and what the expected mechanical properties of the produced part are. For understanding the variables of a metal-forming process, it is best to consider the process as a system, as illustrated in Fig. 2.1 in Chap. 2. The interaction of most significant variables in metal forming are shown, in a simplified manner, in Fig. 3.1. It is seen that for a given billet or blank material and part geometry, the speed of deformation influences strain-rate and flow stress. Deformation speed, part geometry, and die temperature influence the temperature distribution in the formed part. Finally, flow stress, friction, and part geometry determine metal flow, forming load, and forming energy. In steady-state flow (kinematically), the velocity field remains unchanged, as is the case in the extrusion process; in nonsteadystate flow, the velocity field changes continuously with time, as is the case in upset forging.

Formability of Explosive Welded Mg/Al Bimetallic Bar

2016 ◽  
Vol 716 ◽  
pp. 114-120 ◽  
Author(s):  
Sebastian Mróz ◽  
Piotr Szota ◽  
Teresa Bajor ◽  
Andrzej Stefanik
Keyword(s):  
Plastic Deformation ◽  
Strain Rate ◽  
Process Parameters ◽  
Metal Forming ◽  
Explosive Welding ◽  
Physical Modelling ◽  
Main Process ◽  
Compression Tests ◽  
Welding Method

The paper presents the results of physical modelling of the plastic deformation of the Mg/Al bimetallic specimens using the Gleeble 3800 simulator. The plastic deformation of Mg/Al bimetal specimens characterized by the diameter to thickness ratio equal to 1 was tested in compression tests. The aim of this work was determination of the range of parameters as temperature and strain rate that mainly influence on the plastic deformation of Mg/Al bars during metal forming processes. The tests were carried out for temperature range from 300 to 400°C for different strain rate values. The stock was round 22.5 mm-diameter with an Al layer share of 28% Mg/Al bars that had been produced using the explosive welding method. Based on the analysis of the obtained testing results it has been found that one of the main process parameters influencing the plastic deformation the bimetal components is the initial stock temperature and strain rate values.

Study on Metal Forming by Macro-Micro Combine Numerical Analysis

2007 ◽  
Vol 340-341 ◽  
pp. 671-676
Author(s):  
Shao Rui Zhang ◽  
Da Yong Li ◽  
Zhong Wei Yin ◽  
Ying Hong Peng ◽  
Fei Zhou
Keyword(s):  
Metal Forming ◽  
Deformation Process ◽  
Metal Flow ◽  
Yield Function ◽  
Slip Systems ◽  
Crystallographic Slip ◽  
Deformation Properties ◽  
Simulation Results ◽  
True Relation ◽  
Anisotropy Coefficients

It has long been found that the crystal orientations would induce macroscopic anisotropy during deformation process, and then affect the deformation properties of sheet metal. So it is very important to find the true relation between texture distribution and macroscopic anisotropy. In this paper, the anisotropy coefficients of the yield function are fitted by Taylor factor and crystal plastic model. Metal flow is assumed to occur by crystallographic slip on given slip systems within each crystal. Then this simulation results are compared with those of microscopic crystal plastic method.

Metal Flow and Die Filling in Coining of Micro Structures with and without Flash

2005 ◽  
Vol 6-8 ◽  
pp. 631-638 ◽  
Author(s):  
M. Thome ◽  
Gerhard Hirt ◽  
B. Rattay
Keyword(s):  
Numerical Simulations ◽  
Sheet Metal ◽  
Metal Forming ◽  
Production Systems ◽  
Metal Flow ◽  
Small Scale ◽  
Die Filling ◽  
Metal Plates ◽  
Micro Structures ◽  
Channel Structures

The continuing miniaturization of production systems and products poses a challenge for metal forming technologies to produce precise small scale products with microscopic geometric details. Thin metal plates with channel structures are considered to be typical examples for microfluidic applications [1,2]. In this study the coining process of sheet metal to produce channel and rib structures is examined in terms of geometrical die parameters and tool design. For this reason extensive experimental series and numerical simulations have been realized and evaluated.

Severe Plastic Deformation-Key Features, Methods and Application

2020 ◽  
Vol 1003 ◽  
pp. 31-36
Author(s):  
Marko Vilotic ◽  
Li Hui Lang ◽  
Sergei Alexandrov ◽  
Dragisa Vilotic
Keyword(s):  
Mechanical Properties ◽  
Plastic Deformation ◽  
Grain Size ◽  
Tensile Strength ◽  
Severe Plastic Deformation ◽  
Metal Forming ◽  
Good Corrosion Resistance ◽  
Processed Material ◽  
Key Features ◽  
Forming Methods

Compared to conventional metal forming methods, processing by severe plastic deformation is mostly used to improve the mechanical properties and not for the shaping of a product. Processed material usually has an average crystal grain size of less than a micron and as a result, the material exhibits improvements in most of the mechanical properties, such as yield and ultimate tensile strength, microhardness, sufficiently high workability, good corrosion resistance, and implant biocompatibility and others. In this paper, a brief review of the processing by severe plastic deformation was presented, including the benefits, major methods, and the application. Additionally, a brief review of two methods made by authors was made.

scholarly journals FEM analysis of the plastic deformation of the regular arched asperities in the two-stage cold metal forming processes

2019 ◽  
Author(s):  
Leon Kukielka ◽  
Lukasz Bohdal ◽  
Jaroslaw Chodor ◽  
Katarzyna Gotowala ◽  
Pawel Kaldunski ◽  
...  
Keyword(s):  
Plastic Deformation ◽  
Metal Forming ◽  
Fem Analysis ◽  
Two Stage ◽  
Cold Metal

Forming 3D Sheet Metals by Means of Continuous Rolling Method

2009 ◽  
Vol 16-19 ◽  
pp. 570-574 ◽  
Author(s):  
Zhi Qing Hu ◽  
Ming Zhe Li ◽  
Xue Peng Gong ◽  
Zeng Ming Feng
Keyword(s):  
Sheet Metal ◽  
Three Dimensional ◽  
Sheet Metals ◽  
Continuous Rolling ◽  
The Core ◽  
3D Surface ◽  
Multipoint Forming ◽  
Rolling Method ◽  
Novel Method

In this paper, we present a novel method of using the continuous rolling to fabricate three-dimensional sheet metal. The core bendable roller is composed of the flexible axis and the controllable equipment. The transversal shape of the sheet metal can be realized by regulating the controllable equipment to make the axis of bendable roller bent; the longitudinal shape is formed by driving the three bendable rollers rotated and the top roller making a displacement synchronously. Some experiments were performed and typical 3D surface parts were formed. Based on the results of the experiments, the effects of the thickness and the rolling times are discussed. The results of the research will be beneficial to define the parameters and perfect the theory of continuous multipoint forming of multiform 3D parts.

Sign in / Sign up

Export Citation Format

Share Document