Effects of Extrusion Speed on the Deformation of Copper Using ECAP Based on FEM

2015 ◽  
Vol 1088 ◽  
pp. 729-732 ◽  
Author(s):  
Chun Ling Wu ◽  
Zhong Ren Wang ◽  
Wen Zhang
Keyword(s):  
Plastic Deformation ◽  
Effective Stress ◽  
Metal Forming ◽  
Large Strain ◽  
Effective Strain ◽  
Extrusion Speed ◽  
Fine Grained ◽  
Ecap Process ◽  
Friction Extrusion ◽  
Forming Methods

Severe plastic deformation is defined as metal forming methods in which a very large strain is imposed to a bulk in order to make an ultra-fine grained metal. ECAP is one of the most effective methods in SPD. The influences of main parameters on deformation include extrusion route, extrusion pass, die corner, friction, extrusion speed and so on. In this investigation, a model of ECAP process has been developed based on FEM and effects of extrusion speed on effective strain, load and effective stress imposed in the copper road are researched. The results of simulation have shown that lower extrusion speed can lead to higher load of top die and effective stress while the effect of extrusion speed on effective strain of copper road is slight.

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.

Research of Formation Mechanics on Nanostructured Chips by Multi-Deformations Based on Finite Element Method

2014 ◽  
Vol 989-994 ◽  
pp. 352-355
Author(s):  
C.L. Wu ◽  
Z.R. Wang ◽  
Wen Zhang
Keyword(s):  
Finite Element Method ◽  
Plastic Deformation ◽  
Finite Element ◽  
Large Strain ◽  
Effective Strain ◽  
Longitudinal Section ◽  
Rake Angle ◽  
Governing Parameter ◽  
Cutting Velocity ◽  
Mean Strain

Formation of chip is a typical severe plastic deformation progress in machining which is only single deformation stage. The rake angle of tool is governing parameter to create large strain imposed in the chip. Effect of rake angle and deformation times on effective strain, mean strain, strain variety and strain rate imposed in the chip are researched respectively. The result of simulation have shown that the chip with large strain and better uniform of strain along the longitudinal section of chip can be produced with negative rake angle at some lower cutting velocity by multi-deformations in large strain machining.

Finite Element Simulation of Cyclic Channel Die Compression with Route A

2010 ◽  
Vol 44-47 ◽  
pp. 1300-1304
Author(s):  
Feng Jian Shi ◽  
Tao Xu ◽  
Sheng Lu ◽  
Lei Gang Wang
Keyword(s):  
Finite Element ◽  
Large Strain ◽  
Effective Strain ◽  
Central Zone ◽  
Peripheral Zone ◽  
Linear Increase ◽  
Rigid Plastic ◽  
Compression Load ◽  
Fine Grained ◽  
Two Stages

In this paper, effective strain and load were simulated by rigid-plastic finite element method (FEM) during cyclic channel die compression (CCDC) with route A, and the optical microstructure was observed. The results show that large strain can be accumulated in the material by CCDC. The load variation includes two stages, slowly linear increase and rapid increase. At the end of the CCDC, the compression load rises rapidly. Apart from the edges of the specimen, the effective strain is higher in the central region and lower at the surrounding region. The effective strain gradient increases with the number of compression. Grain refinement at the central zone is faster due to the strain inhomogeneity. But the peripheral zone is also refined with the number of CCDC. This illustrates CCDC is a promising method for producing bulk ultra-fine grained materials.

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.

A planar twist channel angular extrusion (PTCAE) as a novel severe plastic deformation method based on equal channel angular extrusion (ECAE) method

2013 ◽  
Vol 228 (12) ◽  
pp. 2246-2250 ◽  
Author(s):  
Mahmoud Shamsborhan ◽  
Ali Shokuhfar
Keyword(s):  
Plastic Deformation ◽  
Severe Plastic Deformation ◽  
Equal Channel Angular Extrusion ◽  
Pure Aluminum ◽  
Effective Strain ◽  
Processing Conditions ◽  
Deformation Method ◽  
Element Analysis ◽  
Ecap Process ◽  
Angular Extrusion

Planar twist channel angular extrusion (PTCAE) is a new severe plastic deformation method to produce bulk ultra-fine-grained materials which is based on conventional equal channel angular extrusion by applying additional planar twist strain in deformation zone of ECAP process and simultaneously imposing larger strain and increasing severe plastic deformation methods efficiency. Plastic deformation characteristics of PTCAE method were analyzed through finite element analysis using Deform 3D V.5 software, processing loads and values of effective strain in different directions of sample were studied for different planar twist angles (α) in comparison with the results of conventional ECAP with the same channel dimension and arc of curvature angles. Die and punch were assumed as rigid bodies, whereas the billet, with dimensions of 10 mm × 10 mm × 70 mm was considered to be deformable pure aluminum. The processing conditions such as friction coefficient, ram speed, mesh size and other factors were held constant to make comparison between the different processing conditions possible. The results indicated that more strain values with more uniform distribution may be achieved after PTCAE method in comparison with the conventional ECAP method. Also, it is observed that in α = 20, the equivalent strain distribution is homogenous approximately in both of vertical and horizontal directions of the cross-section of the sample. Therefore, PTCAE can be considered as a promising severe plastic deformation technique for future industrial applications which can be installed on any standard extrusion equipment without any additional required facilities that are essential in other new severe plastic deformation methods and can be used instead of ECAP process significantly and beneficially.

A Simple Effective Stress Approach for Modeling Rate-Dependent Strength of Soft Clay

2018 ◽  
Vol 140 (4) ◽  
Author(s):  
Jiang Tao Yi ◽  
Yu Ping Li ◽  
Shan Bai ◽  
Yong Fu ◽  
Fook Hou Lee ◽  
...  
Keyword(s):  
Strain Rate ◽  
Effective Stress ◽  
Large Strain ◽  
Soft Clay ◽  
Yield Locus ◽  
Submarine Landslides ◽  
Fine Grained ◽  
Rate Dependent ◽  
Modified Cam Clay ◽  
Free Falling

This paper proposes a simple effective stress method for modeling the strain rate-dependent strength behavior that is experienced by many fine-grained soils in offshore events when subjected to rapid, large strain, undrained shearing. The approach is based on correlating the size of the modified Cam-Clay yield locus with strain rate, i.e., yield locus enlarging or diminishing dependent on the strain rate. A viscometer-based method for evaluating the needed parameters for this approach is provided. The viscometer measurements showed that strain rate parameters are largely independent of water content and agree closely with data from a previous study. Numerical analysis of the annular simple shear situation induced by the viscometer shows remarkable agreement with the experimental data provided the remolding-induced strength degradation effect is accounted for. The proposed method allows offshore foundation installation processes such as dynamically installed offshore anchors, free-falling penetrometer, and submarine landslides to be more realistically analyzed through effective stress calculations.

The Status and Development of ECAP

2014 ◽  
Vol 509 ◽  
pp. 20-24
Author(s):  
Yong Xiang Zhu ◽  
Xiao Dong Luo ◽  
Hao Liu ◽  
Qing Xia Wang
Keyword(s):  
Extrusion Process ◽  
Processing Route ◽  
Large Plastic Deformation ◽  
Extrusion Speed ◽  
Ecap Process ◽  
Ultrafine Grained ◽  
The Status ◽  
The Coefficient Of Friction ◽  
Ultrafine Grained Materials ◽  
Friction Extrusion

ECAP is a large plastic deformation processing technology, ultrafine-grained materials can be prepared using ECAP process. This paper reviews the channel angular extrusion process application in aluminum alloy, copper alloy, magnesium alloy and composite materials and so on. Summarizes the influence of the central angle and mold inside corner radius, processing route, the coefficient of friction , extrusion speed, extrusion temperature, extrusion and steps on the ECAP. Also introduced a more advanced package sets-ECAP and continuous ECAP process.

Thermo-Mechanical Coupled Problems at Finite Strains

2009 ◽  
Vol 283-286 ◽  
pp. 515-520
Author(s):  
M. Vaz ◽  
Pablo A. Muñoz-Rojas ◽  
M.R. Lange ◽  
J. Stahlschmidt
Keyword(s):  
Plastic Deformation ◽  
Metal Forming ◽  
Thermal Effects ◽  
Large Strain ◽  
Low Carbon Steel ◽  
Tensile Loading ◽  
Coupled Problems ◽  
Low Carbon ◽  
Multiplicative Decomposition ◽  
Elastic Plastic

This paper discusses some thermodynamic aspects in association with a large strain/large displacement elastic-plastic formulation aiming at application to metal forming problems. The mechanical solution adopts the multiplicative decomposition of the gradient of deformation into elastic, plastic and thermal components. The approach is illustrated by analysing the thermal effects in the plastic deformation of low-carbon steel specimens subject to tensile loading.

Microstructural Design of an AlMgSi Alloy via ECAP Processing: An Advanced SPD Manufacturing Technique for NC/UFG Materials

2015 ◽  
Vol 1114 ◽  
pp. 143-148
Author(s):  
Nicolae Serban ◽  
Doina Răducanu ◽  
Vasile Danut Cojocaru ◽  
Nicolae Ghiban
Keyword(s):  
Plastic Deformation ◽  
Severe Plastic Deformation ◽  
Grain Refinement ◽  
Shape Change ◽  
Large Strain ◽  
Metallographic Analysis ◽  
Cross Sectional ◽  
Ecap Processing ◽  
Microstructural Design ◽  
Almgsi Alloy

Severe plastic deformation (SPD) has received enormous interest over the last two decades as a method capable of producing fully dense and bulk ultra-fine grained (UFG) and nanocrystalline (NC) materials. Significant grain refinement obtained by SPD leads to improvement of mechanical, microstructural and physical properties. Compared to classical deformation processes, the big advantage of SPD manufacturing techniques, represented in particular by equal channel angular pressing (ECAP) is the lack of shape-change deformation and the consequent possibility to impart extremely large strain. In ECAP processing, the workpiece is pressed through a die in which two channels of equal cross-section intersect at an angle of ϕ and an additional angle of ψ define the arc of curvature at the outer point of intersection of the two channels. As a result of pressing, the sample theoretically deforms by simple shear and retains the same cross-sectional area to allow repeated pressings for several cycles. A commercial AlMgSi alloy was investigated in our study. The specimens were processed at room temperature for multiple passes, using three different ECAP dies. All samples (ECAP processed and as-received) were subjected to metallographic analysis and mechanical testing. Several correlations between the main processing parameters and the resulting microstructural aspect and mechanical features for the processed material were established. It was shown that severe plastic deformation by means of ECAP processing can be used in aluminum alloys microstructural design as an advanced tool for grain refinement in order to attain the desired microstructure and mechanical properties.

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.

Sign in / Sign up

Export Citation Format

Share Document