scholarly journals Evaluation of New Hypothetical Concept (LHSIR) for Die Profile Design for Hydrostatic Extrusion Of AL/MG Compound

2014 ◽  
Vol 7 (1) ◽  
pp. 40-60
Author(s):  
Muhsin J. Jweeg ◽  
Moneer H. Tolephih Al-Saady ◽  
Abdullah Dhayea Assi
Keyword(s):  
Extrusion Process ◽  
Strain Increment ◽  
Hydrostatic Extrusion ◽  
Die Design ◽  
Relative Pressure ◽  
Major Conclusion ◽  
Validity Assessment ◽  
Heat Treated ◽  
Die Profile ◽  
First Time

This paper presents, for the first time, a new developed concept for design of Die pass profile used in hydrostatic-extrusion of Al/Mg compound. The new design criteria proposes a "Linearity" of the Homogeneous Successive Strain Increment Ratios (LHSIR) of the deformed material, instead of the "Constancy" concept (CHSIR) found in literature, as the tool base to generate the profile. The developed profiles were evaluated numerically to assess their relative pressure ratios as the main parameter for performance checking adopting the well-known Upper Bound Approach (UBA). A further developed aspect for the velocity field proposition is successfully made to carry out the necessary tedious computations. 12 different samples of commercial tool steel were CNC-manufactured, heat treated and tested to Al/Mg compound, from lead alloy, for sake of comparison and validity assessment. The major conclusion comes out of this work claims that a small variance in the classical constancy criteria of the Die design is very sensitive to change the expected levels of the relative pressure ratios of the extrusion process.

A Novel Method for 3D-Die Design in the Extrusion Process Using Equi-Potential Lines

2013 ◽  
Vol 585 ◽  
pp. 67-75 ◽  
Author(s):  
Seyed A. Tabatabei ◽  
M.K. Besharati Givi ◽  
Karen Abrinia ◽  
Peyman Karami ◽  
V. Zal ◽  
...  
Keyword(s):  
Product Quality ◽  
Cross Sections ◽  
Deformation Zone ◽  
Extrusion Process ◽  
Die Design ◽  
Extrusion Pressure ◽  
Entry And Exit ◽  
Novel Method ◽  
First Time ◽  
Minimum Work

Die shape plays a key role in extrusion process through widely affects on the extrusion pressure and product quality. Therefore, prediction of the optimal die shape is the main objective for an effective extrusion process. In this study, the notion of Equi-Potential Lines (EPLs) was applied to 3D-die designing in extrusion process for the first time. To implement the analogy in the extrusion, the initial and final shapes were considered and two different potentials were assigned to them, and then EPLs were drawn between two shapes that show the minimum work path between the entry and exit cross sections. The drawn EPLs were connected to build up a 3D-die. The effectiveness of the proposed method was examined experimentally, by comparing the results between the designed die and the linear die (with the linear curve for the deformation zone). It was found that there was acceptable reduction in extrusion pressure for the designed die.

scholarly journals Mechanochemical Synthesis and Nitrogenation of the Nd1.1Fe10CoTi Alloy for Permanent Magnet

Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 3854
Author(s):  
Hugo Martínez Sánchez ◽  
George Hadjipanayis ◽  
Germán Antonio Pérez Alcázar ◽  
Ligia Edith Zamora Alfonso ◽  
Juan Sebastián Trujillo Hernández
Keyword(s):  
Mechanochemical Synthesis ◽  
Applied Field ◽  
Volume Fraction ◽  
Synthesis Method ◽  
High Energy ◽  
Direction Parallel ◽  
Best Value ◽  
Heat Treated ◽  
Bcc Phase ◽  
First Time

In this work, the mechanochemical synthesis method was used for the first time to produce powders of the nanocrystalline Nd1.1Fe10CoTi compound from Nd2O3, Fe2O3, Co and TiO2. High-energy-milled powders were heat treated at 1000 °C for 10 min to obtain the ThMn12-type structure. Volume fraction of the 1:12 phase was found to be as high as 95.7% with 4.3% of a bcc phase also present. The nitrogenation process of the sample was carried out at 350 °C during 3, 6, 9 and 12 h using a static pressure of 80 kPa of N2. The magnetic properties Mr, µ0Hc, and (BH)max were enhanced after nitrogenation, despite finding some residual nitrogen-free 1:12 phase. The magnetic values of a nitrogenated sample after 3 h were Mr = 75 Am2 kg–1, µ0Hc = 0.500 T and (BH)max = 58 kJ·m–3. Samples were aligned under an applied field of 2 T after washing and were measured in a direction parallel to the applied field. The best value of (BH)max~114 kJ·m–3 was obtained for 3 h and the highest µ0Hc = 0.518 T for 6 h nitrogenation. SEM characterization revealed that the particles have a mean particle size around 360 nm and a rounded shape.

scholarly journals Analysis and optimization of cooling channels performances for industrial extrusion dies

2021 ◽  
Author(s):  
Riccardo Pelacci ◽  
Marco Negozio ◽  
Barbara Reggiani ◽  
Lorenzo Donati ◽  
Luca Tomesani
Keyword(s):  
Liquid Nitrogen ◽  
Numerical Models ◽  
Extrusion Process ◽  
Die Design ◽  
Design Stage ◽  
Fe Model ◽  
Cooling Efficiency ◽  
Channel Design ◽  
Liquid Nitrogen Cooling ◽  
Experimental Trials

Liquid nitrogen cooling is widely used in the extrusion industrial practice in order to increase the production rate, to reduce the die temperature and to avoid defects on the profile exit surfaces resulting from an excessive heating. However, the efficiency of the cooling is deeply affected by position and design of the liquid nitrogen channel so that numerical modelling is gaining an increasing industrial interest in relation to the possibility offered to optimize the channel design without expensive and time-consuming experimental trials. In this work, a numerical FE model developed within COMSOL Multiphysics® is proposed and validated against experimental trials performed in industrial environment. The model combines the 3D simulation of the extrusion process with a 1D model of the cooling channel thus allowing the testing of a number of different solutions at the die design stage. The global aim of this work is the assessment of the liquid nitrogen cooling efficiency in the extrusion of an industrial aluminum profile and the proof of the potentials offered by numerical models to get an optimized channel design in terms of cooling efficiency, die thermal balancing and reduction of liquid nitrogen consumption.

Design and Experimental Verification of a New Direct Cold Drawing Die for Section Rod From Round Bar

1999 ◽  
Author(s):  
Liping Wang
Keyword(s):  
Computer Aided Design ◽  
Cold Drawing ◽  
Die Design ◽  
Machining Process ◽  
Drawing Die ◽  
Die Profile ◽  
The Mean ◽  
Aided Design ◽  
Manufacturing Parameters ◽  
Advanced Computer

Abstract This paper presents the design and verification of a new direct cold drawing die used for drawing of hexagon/square section rods from round bars. Advanced computer-aided design and analysis tools are utilized to assist in the design of die profile and manufacturing parameters. The strain gage method is adopted to measure the mean drawing force and verify the die design and machining process.

scholarly journals Physicochemical, Rheological, and Morphological Characteristics of Products from Traditional and Extrusion Nixtamalization Processes and Their Relation to Starch

2020 ◽  
Vol 2020 ◽  
pp. 1-12 ◽  
Author(s):  
Carlos Martín Enríquez-Castro ◽  
Patricia Isabel Torres-Chávez ◽  
Benjamín Ramírez-Wong ◽  
Armando Quintero-Ramos ◽  
Ana Irene Ledesma-Osuna ◽  
...  
Keyword(s):  
Resistant Starch ◽  
Morphological Characteristics ◽  
Extrusion Process ◽  
Quality Parameter ◽  
Particle Sizes ◽  
Corn Flour ◽  
Viscoelastic Parameters ◽  
Size Index ◽  
Parameter Values ◽  
First Time

The aim of this study was to compare the physicochemical, rheological, and morphological characteristics of corn, nixtamalized flour, masa, and tortillas from the traditional nixtamalization process (TNP) and the extrusion nixtamalization process (ENP) and their relationship with starch. The traditional and extrusion processes were carried out using the same variety of corn. From both processes, samples of ground corn, nixtamalized flour, masa, and tortillas were obtained. The extrusion process produced corn flour with particle sizes smaller (particle size index, PSI = 51) than that of flour produced by the traditional nixtamalization process (PSI = 44). Masa from the TNP showed higher modulus of elasticity (G′) and viscosity (G″) values than that off masa from the ENP. Furthermore, in a temperature sweep test, masa from the TNP showed a peak in G′ and G″, while the masa from the ENP did not display these peaks. The ENP-produced tortillas had higher resistant starch contents and comparable firmness and rollability to those from the TNP but lower quality parameter values. A comparison of the products’ physicochemical properties obtained by the two processes shows the importance of controlling the damage to starch during the milling and extrusion processes to obtain tortillas of better quality. For the first time, we propose the measurement of the viscoelastic parameters G′ and G″ in temperature sweep mode to monitor changes in the degree of starch damage.

Sign in / Sign up

Export Citation Format

Share Document