scholarly journals Analysis of processing variables in Equiangular Channel Press deformations

2021 ◽  
Vol 10 (16) ◽  
pp. e140101623101
Author(s):  
Reinan Tiago Fernandes dos Santos ◽  
Wilton Walter Batista
Keyword(s):  
Deformation Process ◽  
Promising Technique ◽  
Electronic Library ◽  
Pressing Temperature ◽  
Bending Angle ◽  
Practical Applications ◽  
Ecap Process ◽  
Pure Metals ◽  
Number Of Passes ◽  
Microstructure Of The Material

Equiangular Channel Pressing (ECAP) is by far the most promising technique, by the severe plastic deformation (SPD) method, being able to produce large volumes of materials sufficient for practical applications. The ECAP process can be repeated until refining saturation is reached, leading to large amounts of shear strain. The reason behind the exceptional properties obtained in materials processed by ECAP was attributed to the microstructure of the material obtained in this deformation process. This work investigated the ECAP strain variables in the literature in order to analyze the effect of each of these on the microstructure of processed materials. The articles were collected from the following databases: ScienceDirect and the Scientific Electronic Library Online (SciELO) electronic library, as they include national and international literature. Based on the results found, it could be seen that several parameters must be analyzed to deform pure metals and alloys, to refine the microstructure, such as bending angle and channel angle of the strain matrix, number of passes, and pressing temperature. It was possible to verify that changes in these variables configure changes in the microstructure.

scholarly journals PERUBAHAN NILAI KEKERASAN DAN KONDUKTIVITAS LISTRIK ALUMINIUM AKIBAT PROSES EQUAL CHANNEL ANGULAR PRESSING (ECAP)

ROTASI ◽  
2014 ◽  
Vol 16 (4) ◽  
pp. 41
Author(s):  
Rusnaldy Rusnaldy ◽  
Norman Iskandar ◽  
Muhammad Khairul Rais ◽  
Wisnu Tri Erlangga
Keyword(s):  
Electrical Conductivity ◽  
Plastic Deformation ◽  
Equal Channel Angular Pressing ◽  
Hardness Test ◽  
Hardness Measurement ◽  
Optical Microscope ◽  
Pure Aluminium ◽  
Angular Pressing ◽  
Ecap Process ◽  
Number Of Passes

In current study, Equal Channel Angular Pressing (ECAP) process was applied to pure aluminium rod. The effect of the number of passes on hardness and electrical conductivity ECAP samples was investigated. The dimensions of ECAP die for 12 mmm diameter workpieces are designed with intersect angle of 120o. The experiments were carried out by using samples cut from an ingot and a rod and machined to a size of 12 mm in diameter and 50 mm in length. The workpiece was pressed into the ECAP die up to 7 passes at room temperature.After deformation, all samples were subjected to a hardness test, an electrical conductivity test and for optical microscope study. The hardness measurement of the ECAP samples suggested that enhanced hardness would be obtained by repeating ECAP process.Increasing the electrical conductivity of the ECAP samples indicatesthat there is no dislocation formation due to increasing plastic deformation in ECAP process

scholarly journals Portable device for thermal nondestructive testing of hidden corrosion in metallic shells by using a LED heat source

2019 ◽  
Vol 121 ◽  
pp. 01014
Author(s):  
D.A. Simonov ◽  
A.I. Moskovchenko
Keyword(s):  
Nondestructive Testing ◽  
Petrochemical Industry ◽  
Spectral Band ◽  
Promising Technique ◽  
Material Loss ◽  
Practical Applications ◽  
High Productivity ◽  
Safety Requirements ◽  
Thermal Nondestructive Testing ◽  
Hidden Corrosion

Thermal nondestructive testing (NDT) is a promising technique for detecting hidden corrosion in metallic shells, such as above-ground tanks, pipes, containers, etc., due to its high productivity and illustrativeness. However, the use of powerful halogen lamps in practical applications is questionable because of reflected radiation and safety requirements. In this paper, a portable thermal NDT device using a LED heater is described. Such heaters operate at wavelengths which are beyond of the spectral band of contemporary infrared imagers. Also, they can use a battery as a power supply thus meeting in-field requirements, for example, in the petrochemical industry. Depending on defect size and material loss, the developed portable thermal NDT device can detect corrosion in steel shells with thickness up to 8 mm.

Mechanical Properties of Al6061 Processed by Equal Channel Angular Pressing

2012 ◽  
Vol 585 ◽  
pp. 392-396 ◽  
Author(s):  
Ankit Sahai ◽  
Rahul Swarup Sharma ◽  
K. Hans Raj ◽  
Narinder Kumar Gupta
Keyword(s):  
Mechanical Properties ◽  
Equal Channel Angular Pressing ◽  
Manufacturing Industry ◽  
High Strength ◽  
Load Variations ◽  
Outer Corner ◽  
Angular Pressing ◽  
Ecap Process ◽  
Circular Specimen ◽  
Number Of Passes

The severe plastic deformation (SPD) is an effective approach for producing bulk nanostructured materials. The Equal Channel Angular Pressing (ECAP) is the most efficient SPD solution for achieving ultra-fined grained (UFG) material as billet undergoes severe and large deformation. The process parameters of ECAP (Channel Angle, angle of curvature, friction, number of passes, etc) influences major impact on the properties. In present work, the ECAP process is performed by pressing a specimen through a die consisting of two intersecting channels meeting at an angle φ and outer corner meeting at an angle ψ. Experiments with a circular specimen of Al6061 were conducted to investigate the changes in mechanical properties upto 2 passes. 3-D finite element simulations were also performed using metal forming software FORGE to study the evolution of strain in the specimen during the ECAP process. Simulation results were investigated by comparing them with experimental measured data in terms of load variations. The present work clearly shows that ECAP caused accentuated increase in Al6061 hardness and tensile strength during multi-pass processing. This study is beneficial in developing high quality, high strength products in manufacturing industry on account of its ability to change microstructure of materials.

Behavior evaluation and effects of different lubricants in ECAP process

2017 ◽  
Vol 69 (5) ◽  
pp. 701-707
Author(s):  
Seyed Husein Hasani Najafabadi ◽  
Ali Akbar Lotfi Neyestanak ◽  
Saeed Daneshmand
Keyword(s):  
Friction Coefficient ◽  
Process Parameters ◽  
Effective Strain ◽  
Mesh Size ◽  
Industrial Applications ◽  
Zinc Stearate ◽  
Content Type ◽  
Practical Applications ◽  
Angular Pressing ◽  
Ecap Process

Purpose The purpose of equal channel angular pressing (ECAP) is producing ultra-fine grain materials. In practical applications, it is important to understand and predict effect of different process parameters on deformed parts. One of the most important process parameters is friction coefficient. Behavior evaluation of different lubricants in the ECAP process is the aim of this research. Design/methodology/approach The present study concerns the experimental measurements of the effective strain by means of gridded parts for three different lubricants, graphite, molybdenum disulfide and zinc stearate, to evaluate friction coefficient in ECAP process. Mesh size was 2 × 2 mm2 and embedded in parts made of AL2024; process was done in ambient temperature, and parts were in annealed situation. After the process, strain measured by optical and analytical methods for evaluation of lubricants’ behavior with different friction coefficients. Findings This study shows that zinc stearate has better effects rather than other lubricants in ECAP process and ECAPed parts. Originality/value The fatal challenge for researchers and industrial applications of ECAP process is lubrication. This research is a guide for scientists and engineers (in the future applications) to reduce and control bad frictional effects, produce better parts (more strain homogenous parts), prevent die failures and decrease press tonnage in ECAP process.

scholarly journals Plastic Folding of Bar Stocks of Round and Barrel-Shaped Sections

2022 ◽  
Author(s):  
O.S. Zhelezkov
Keyword(s):  
Finite Element ◽  
Finite Element Modeling ◽  
Cross Sections ◽  
Deformation Process ◽  
Strain State ◽  
Stress Strain ◽  
Plastic Bending ◽  
Bending Angle ◽  
Element Modeling ◽  
Stress Strain State

Abstract. Research has been carried out on the process of plastic folding of bar stocks with round and barrel-shaped cross-sections. The dependence of the movement of the movable tool on the bending angle has been established. The force parameters of the deformation process and the stress-strain state in the bending workpiece are determined based on the results of finite element modeling of plastic bending.

Principles of Nonequal Channel Angular Pressing

2010 ◽  
Vol 132 (3) ◽  
Author(s):  
Arman Hasani ◽  
László S. Tóth ◽  
Benoît Beausir
Keyword(s):  
Deformation Process ◽  
Flow Line ◽  
Deformation Field ◽  
Machining Process ◽  
Exit Channel ◽  
Angular Pressing ◽  
Ecap Process ◽  
Plastic Deformation Process ◽  
Hydrostatic Stresses ◽  
The Stability

A variant of the equal channel angular pressing (ECAP) process is examined in this paper where the channels are of rectangular shape with different thicknesses while the widths of the channels are the same. The process is named nonequal channel angular pressing and it is similar to the earlier introduced dissimilar channel angular pressing (DCAP) process. In DCAP, however, the diameters are near values, with the exit channel being slightly larger, while in NECAP, the exit channel is much smaller attributing several advantages to nonequal channel angular pressing (NECAP) with respect to ECAP. In this work an analysis is performed to determine the strain mode in a 90 deg NECAP die. A new flow line function is also presented to better describe the deformation field. The proposed flow line function is validated using finite element simulations. A comparison is made between ECAP and NECAP. Finally, texture predictions are presented for NECAP of fcc polycrystals. The advantages of this severe plastic deformation process are the following: (i) significantly larger strains can be obtained in one pass with respect to the classical ECAP process, (ii) grains become more elongated that enhances their fragmentation, and (iii) large hydrostatic stresses develop that improve the stability of the deformation process for difficult-to-work materials. The results obtained concerning the deformation field are also applicable in the machining process for the plastic strains that imparted into the chips.

scholarly journals Spring-back effect during multi-pass bending of sheet blanks

2019 ◽  
Vol 135 ◽  
pp. 01066
Author(s):  
Volodymyr Kukhar ◽  
Mykyta Nahnibeda ◽  
Oleksii Radushev
Keyword(s):  
Experimental Research ◽  
Thickness Ratio ◽  
Basic Information ◽  
Spring Back ◽  
Bending Angle ◽  
The Difference ◽  
Geometric Quality ◽  
Back Angle ◽  
Number Of Passes

A significant factor, which leads to the discrepancy of the final sizes of the bent sheet parts to their drawings is the springing of the sheet blank during bending. At the same time, the springing during multi-pass bending is not sufficiently studied. The purpose of the work is to obtain the graphical and mathematical dependencies for descriptions of the resultative spring-back angle of the blanks at the multi-pass bending, taking into account the width of the blank, number of passes, and pre-bending angle at each preliminary pass. The paper describes the basic information about the difference between the spring-back angle for one-pass or multi-pass bending. In the course of the study it is shown that during calculations of forming and preventive prediction of the geometric quality of bending shapes it is necessary to take into account properties of the blank material, as well as the angles of the prebends and the width to thickness ratio of the blank. A methodology of experimental research was developed for determining the spring-back angle during multi-pass bending in three bending dies with 109°, 91° and 72° pass-by-pass reducing angles.

Effects of Inner Corner Angle on Strain Distribution of ECAPed Aluminum Alloy

2013 ◽  
Vol 743 ◽  
pp. 231-234
Author(s):  
Xi Liang Chen ◽  
Qing Nan Shi
Keyword(s):  
Strain Distribution ◽  
Deformation Process ◽  
Effective Strain ◽  
High Strength ◽  
Deformation Method ◽  
Corner Angle ◽  
Angular Pressing ◽  
Ecap Process ◽  
Ultrafine Grained ◽  
Ultrafine Grained Materials

Ultrafine-grained materials have excellent mechanical properties, which include the high strength and toughness. Equal channel angular pressing (ECAP) is one kind of severe plastic deformation method to make ultrafine-grained metals. The ECAP processes are simulated by finite element method (FEM) in this work. The effects of inner corner angle on strain distribution during the deformation process are numerically analyzed. The evolutions of effective strain on three points of different deformation are compared. The results show that the deformation becomes severe on each point when the inner corner angle is less than 90o, which is different from the situation when the inner corner angle is equal to or greater than 90o. The results are useful for improving the ECAP process to make the structure of metals homogenous.

scholarly journals THE EFFECT OF ECAP PROCESSING TO HARDNESS, SURFACE MORPHOLOGI, AND CORROSION RESISTANCE OF 6061 ALUMINIUM ALLOYS

Metalurgi ◽  
2021 ◽  
Vol 36 (2) ◽  
Author(s):  
Vinda Puspasari ◽  
I. Nyoman Gede P. A. ◽  
Efendi Mabruri ◽  
Satrio Herbirowo ◽  
Edy Priyanto Utomo
Keyword(s):  
Grain Size ◽  
Corrosion Resistance ◽  
Corrosion Behaviour ◽  
Bulk Material ◽  
Ecap Processing ◽  
Al 6061 ◽  
Fine Grain ◽  
Ecap Process ◽  
Mechanical And Physical Properties ◽  
Number Of Passes

Al-Mg-Si alloys (6xxx) has been widely used as structural materials in building and vehicles because of its excellent strength and corrosion resistance. The improvement of fine grain microstructure which can increase mechanical and physical properties become an interesting field in recent research.. Equal channel angular press is the most promising method to apply severe plastic deformation (SPD) which can produce ultra-fine grain in the bulk material without residual porosity. This study presents some experiments results on the effect of ECAP number of passes variation to the hardness, microstructure, and corrosion behaviour of Al 6061 alloys. The samples were annealed in the furnace with argon gas environment at 530°C for 4 hours and then immersed in liquid nitrogen for 5 minutes before ECAP process. The ECAP process was done with Bc route using dies with 120° of internal channel angle and pass variation of 1, 2, 3, and 4. The optimum hardness is 107.58 HRB in Al 6061 samples with 3 passes of ECAP. The increasing ECAP number of passes leads to a significant grain size reduction from 0 way pass, the grain size is around 10 µm, while for a 4 way pass, the grain size is around 2.5 µm. The corrosion resistance of Al 6061 alloys increased with the increasing number of passes in ECAP process.

A set of constitutive functions for dried body to predict entire deformation process of ceramic products during firing

2017 ◽  
Vol 34 (8) ◽  
pp. 2668-2697
Author(s):  
Seishiro Matsubara ◽  
Kenjiro Tarada ◽  
Takaya Kobayashi ◽  
Toshiyuki Saitou ◽  
Manabu Umeda ◽  
...  
Keyword(s):  
Elastic Modulus ◽  
Deformation Process ◽  
Design Methodology ◽  
Mechanical Analysis ◽  
Test Results ◽  
Densification Rate ◽  
Content Type ◽  
Practical Applications ◽  
Mechanical Deformations ◽  
Practical Implications

Purpose The purpose of this paper is to propose a set of constitutive functions for dried bodies for accurate prediction of the entire deformation process of ceramic products during firing and to present relevant methods for determining their coefficients from a series of respective thermo-mechanical analysis (TMA) tests. Design/methodology/approach The function forms of the sintering-induced strain rate, viscoplastic multiplier and elastic modulus are formulated in order with reference to empirical data of relative densities. Separate TMA tests are conducted to identify their coefficients, while a stairway thermal cycle test is carried out to identify the parameters in the densification rate. Then, various finite element analyses (FEA) are performed for accuracy confirmation. Findings The performances of the present constitutive functions along with the identified material parameters were validated in comparison with the relevant test results. It has then been confirmed that these functions enable us to some extent to accurately estimate the non-mechanical and mechanical deformations of dried bodies during firing. Also, by performing FEA of an actual sanitary ware product, the applicability and capability of the proposed set of constitutive functions could be demonstrated. Practical implications The present methodology with the proposed constitutive functions is a simple, but reliable and practical approach for simulating the deformation process of arbitrary ceramic products subjected to firing and applicable for practical applications in various engineering fields. Originality/value The constitutive functions of the viscoplastic multiplier and elastic modulus, which enable us to properly characterize the mechanical behavior of dried bodies subjected to firing, are originally formulated in analogy with that of the sintering-induced strain.

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