skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Analysis of Material Flow in Screw Extrusion of Aluminum

Abstract

Screw extrusion of aluminum is a new process for production of aluminum profiles. The commercial potential could be large. Little experimental and numerical work has been done with respect to this process.The material flow of hot aluminum in a screw extruder has been analyzed using finite element formulations for the non-Newtonian Navier-Stokes equations. Aluminum material properties are modeled using the Zener-Holloman material model. Effects of stick-slip conditions are investigated with respect to pressure build up and mixing quality of the extrusion process.The numerical results are compared with physical experiments using an experimental screw extruder.

Authors:
; ; ;  [1]
  1. Department of Engineering Design and Materials, NTNU (Norway)
Publication Date:
OSTI Identifier:
21366802
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1252; Journal Issue: 1; Conference: NUMIFORM 2010: 10. international conference on numerical methods in industrial forming processes dedicated to Professor O. C. Zienkiewicz (1921-2009), Pohang (Korea, Republic of), 13-17 Jun 2010; Other Information: DOI: 10.1063/1.3457646; (c) 2010 American Institute of Physics
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALUMINIUM; ALUMINIUM ALLOYS; EXTRUSION; FINITE ELEMENT METHOD; NAVIER-STOKES EQUATIONS; SLIP; ALLOYS; CALCULATION METHODS; DIFFERENTIAL EQUATIONS; ELEMENTS; EQUATIONS; FABRICATION; MATERIALS WORKING; MATHEMATICAL SOLUTIONS; METALS; NUMERICAL SOLUTION; PARTIAL DIFFERENTIAL EQUATIONS

Citation Formats

Haugen, Bjoern, Oernskar, Magnus, Welo, Torgeir, and Wideroee, Fredrik. Analysis of Material Flow in Screw Extrusion of Aluminum. United States: N. p., 2010. Web. doi:10.1063/1.3457646.
Haugen, Bjoern, Oernskar, Magnus, Welo, Torgeir, & Wideroee, Fredrik. Analysis of Material Flow in Screw Extrusion of Aluminum. United States. doi:10.1063/1.3457646.
Haugen, Bjoern, Oernskar, Magnus, Welo, Torgeir, and Wideroee, Fredrik. 2010. "Analysis of Material Flow in Screw Extrusion of Aluminum". United States. doi:10.1063/1.3457646.
@article{osti_21366802,
title = {Analysis of Material Flow in Screw Extrusion of Aluminum},
author = {Haugen, Bjoern and Oernskar, Magnus and Welo, Torgeir and Wideroee, Fredrik},
abstractNote = {Screw extrusion of aluminum is a new process for production of aluminum profiles. The commercial potential could be large. Little experimental and numerical work has been done with respect to this process.The material flow of hot aluminum in a screw extruder has been analyzed using finite element formulations for the non-Newtonian Navier-Stokes equations. Aluminum material properties are modeled using the Zener-Holloman material model. Effects of stick-slip conditions are investigated with respect to pressure build up and mixing quality of the extrusion process.The numerical results are compared with physical experiments using an experimental screw extruder.},
doi = {10.1063/1.3457646},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1252,
place = {United States},
year = 2010,
month = 6
}
  • Abstract In the present study, response surface method (RSM) and genetic algorithm (GA) were used to study the effects of process variables like screw speed, rpm (x1), L/D ratio (x2), barrel temperature ( C; x3), and feed mix moisture content (%; x4), on flow rate of biomass during single-screw extrusion cooking. A second-order regression equation was developed for flow rate in terms of the process variables. The significance of the process variables based on Pareto chart indicated that screw speed and feed mix moisture content had the most influence followed by L/D ratio and barrel temperature on the flow rate.more » RSM analysis indicated that a screw speed>80 rpm, L/D ratio> 12, barrel temperature>80 C, and feed mix moisture content>20% resulted in maximum flow rate. Increase in screw speed and L/D ratio increased the drag flow and also the path of traverse of the feed mix inside the extruder resulting in more shear. The presence of lipids of about 35% in the biomass feed mix might have induced a lubrication effect and has significantly influenced the flow rate. The second-order regression equations were further used as the objective function for optimization using genetic algorithm. A population of 100 and iterations of 100 have successfully led to convergence the optimum. The maximum and minimum flow rates obtained using GA were 13.19 10 7 m3/s (x1=139.08 rpm, x2=15.90, x3=99.56 C, and x4=59.72%) and 0.53 10 7 m3/s (x1=59.65 rpm, x2= 11.93, x3=68.98 C, and x4=20.04%).« less
  • The aim of this work is to design and to improve the geometry of a porthole-die for the production of aluminum components by means of 3D FEM simulations. In fact, the use of finite element models will allow to investigate the effects of the die geometry (webs, extrusion cavity) on the material flow and on the stresses acting on the die so to reduce the die wear and to improve the tool life. The software used to perform the simulations was a commercial FEM code, Deform 3D. The technological data introduced in the FE model have been furnished by METRAmore » S.p.A. Company, partner in this research. The results obtained have been considered valid and helpful by the Company for building a new optimized extrusion porthole-die.« less
  • Plastics, starting from inexpensive mass-produced articles to technical high-end applications, are being used in ever more areas of life. The main drivers are their flexible product properties and the resultant broad application possibilities. To be able to offer plastic products inexpensively and conserve the environment at the same time, more and more attention is being paid to plastics recycling. Polyethylene terephthalate – in short PET – is of particular significance here because of its frequent application in the film and packaging industry and its special material properties. The recycling of PET, however, can only be carried out a limited numbermore » of times because it’s processing necessarily results in both thermal and mechanical stresses on the material. This is the basis for the reactions at molecular level, which result in a shortening of the molecule chains (material degradation) and exert a negative effect on the product properties. The aim of this study is to identify the factors that influence the material degradation of PET in twin-screw extrusion. To do this, various screw configurations and different speed and throughput conditions are examined in a series of experiments. Furthermore, material specimens are removed along the length of the screw in order to evaluate the influence of individual screw sections. By determining the intrinsic viscosity of the specimens, it is possible to measure the mean molecular weight and thus the material damage. Based on the test results, guidelines are drawn up for the compounding of PET so as to ensure as little damage as possible to the material.« less
  • Aluminum extension applies to industrial structure, light load, framework rolls and conveyer system platform. Many factors must be controlled in processing the non-specific engineering structure (hollow shape) of the aluminum alloy during extrusion, to obtain the required plastic strain and desired tolerance values. The major factors include the forming angle of the die and temperature of billet and various materials. This paper employs rigid-plastic finite element (FE) DEFORM 3D software to investigate the plastic deformation behavior of an aluminum alloy (A6061, A5052, A3003) workpiece during extrusion for the engineering structure of the aluminum alloy. This work analyzes effective strain, effectivemore » stress, damage and die radius load distribution of the billet under various conditions. The analytical results confirm the suitability of the current finite element software for the non-specific engineering structure of aluminum alloy extrusion.« less
  • Changes in proximate composition of fish and rice flour coextrudates like moisture, protein, and fat content were studied with respect to extrusion process v ariables like barrel temperature, x1 (100–200 degrees C); screw speed, x2 (70–110 rpm); fish content of the feed, x3 (5–45 percent); and feed moisture content, x4 (20–60 percent). Experiments were conducted at five levels of the process variables based on rotatable experimental design. Response surface models (RSM) were developed that adequately described the changes in moisture, protein, and fat content of the extrudates based on the coeff icient of determination (R2) values of 0.95, 0.99, andmore » 0.94. ANOVA analysis indicated that extrudate moisture content was influenced by x4, protein content by x1 and x3, and fat content by x3 and x4 at P < 0.001. Trends based on response surf ace plots indicated that the x1 of about 200 degrees C, x2 of about 90 rpm, x3 of about 25%, and x4 of about 20% minimized the moisture in the extrudates. Protein content was maximized at x1 of 100 degrees C, x2 > 80 rpm, x3 of about 45 percent, and x4 > 50 percent, and fat content was minimized at x1 of about 200 degrees C, x2 of about 85–95 rpm, x3 < 15 percent, and x4 of about >50 percent. Optimized process variables based on a genetic algorithm (GA) for minimum moisture and fat content and maximum protein content were x1 = 199.86, x2 = 109.86, x3 = 32.45, x4 = 20.03; x1 = 199.71, x2 = 90.09, x3 = 15.27, x4 = 58.47; and x1 = 102.97, x2 = 107.67, x3 = 44.56, x4 = 59.54. The predicted values were 17.52 percent, 0.57 percent, and 46.65 percent. Based on the RSM and GA analy sis, extrudate moisture and protein content was influenced by x1, x3, and x4 and fat content by x2, x3, and x4.« less