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The paper aims to use the finite volume method widely used in computational fluid dynamics to avoid the serious remeshing and mesh distortion during aluminium profile extrusion processes simulation when using the finite element method. Block-structured grids are used to fit the complex domain of the extrusion. A finite volume method (FVM) model for aluminium extrusion numerical simulation using non-orthogonal structured grids was established.

The influences of the elements ' nonorthogonality on the governing equations discretization of the metal flow in aluminium extrusion processes were fully considered to ensure the simulation accuracy. Volume-of-fluid (VOF) scheme was used to catch the free surface of the unsteady flow. Rigid slip boundary condition was applied on non-orthogonal grids.

This paper involved a simulation of a typical aluminium extrusion process by the FVM scheme. By comparing the simulation by the FVM model established in this paper with the ones simulated by the finite element method (FEM) software Deform-3D and the corresponding experiments, the correctness and efficiency of the FVM model for aluminium alloy profile extrusion processes in this paper was proved.

This paper uses the FVM widely used in CFD to calculate the aluminium profile extrusion processes avoiding the remeshing and mesh distortion during aluminium profile extrusion processes simulation when using the finite element method. Block-structured grids with the advantage of simple data structure, small storage and high numerical efficiency are used to fit the complex domain of the extrusion.

The purpose of this paper is to join AA5052 to AISI 1006 steel sheets using the spot friction forming technique.

A steel sheet was pre-holed with a diameter of 4.8 mm and pre-threaded with a single internal M6 thread. Lap joint configuration was used so that the aluminium specimen was put over steel. A rotating tool with a 10 mm diameter was used for the joining process. A Taguchi method was used to design three process parameters (plunging tool depth, rotating speed and preheating time), with three levels for each parameter. The effect of the process parameters on the joint shear strength was analysed. The macrostructure, microstructure and scanning electron microscope of the joint were investigated. The temperature distribution during the joining process was recorded.

The formed aluminium was extruded through the steel hole and penetrated through the thread slot. A mechanical interlock was achieved between the extruded aluminium and the steel. The plunging depth of the tool exhibited a significant effect on the joint shear strength. The joint efficiency increased gradually as the plunging depth increased. Two modes of failure were found shear and pull-out. The maximum temperature during the process reached 50 per cent of aluminium’s melting point.

For the first time, AA5052 was joined with AISI 1006 steel using a friction spot forming technique with an excellent joint efficiency.

To provide a selective bibliography for researchers working with bulk material forming (specifically the forging, rolling, extrusion and drawing processes) with sources which can help them to be up‐to‐date.

A range of published (1996‐2005) works, which aims to provide theoretical as well as practical information on the material processing namely bulk material forming. Bulk deformation processes used in practice change the shape of the workpiece by plastic deformations under forces applied by tools and dies.

Provides information about each source, indicating what can be found there. Listed references contain journal papers, conference proceedings and theses/dissertations on the subject.

It is an exhaustive list of papers (1,693 references are listed) but some papers may be omitted. The emphasis is to present papers written in English language. Sheet material forming processes are not included.

A very useful source of information for theoretical and practical researchers in computational material forming as well as in academia or for those who have recently obtained a position in this field.

There are not many bibliographies published in this field of engineering. This paper offers help to experts and individuals interested in computational analyses and simulations of material forming processes.

A local company producing aluminum profile encounters frequent failures to bridge dies. In total, 22 dies failed within a year, entailing production disruptions and extensive downtimes. Bridges usually exhibit cracks on the ribs. The failure analysis of the failed parts has been performed in order to propose solution for correct and economical process. The paper aims to discuss these issues.

Recorded history was collected regarding tool’s material selection, manufacturing conditions, usage and service. A representative failed bridge was in depth analyzed. The piece was optically inspected. Rockwell hardness measurements and chemical analysis were performed. The paper is focussed on the microscopic examination of the failed parts. Specimens were cut from bridge’s ribs. Areas including cracks were analyzed on the cross section of the samples by optical and scanning electron microscopy. Local chemical analysis was made by X-ray microanalysis.

Design, deficiency and improper maintenance are considered to be responsible for the systematic die damage. Prolonged preheating duration and poor quality surfaces before nitriding render dies premature unusable. The preheating duration should be controlled and protective atmosphere should be used. Furthermore, it is suggested to protect the ribs during nitriding as a preventive measure against crack initiation. The bridge’s geometry can be improved by fabricating ribs with larger radii. A finer polishing is recommended.

The present analysis resolved a serious deficiency in extrusion production. Extended research has been conducted in the field of aluminum extrusion dies, nevertheless, the present work presents new metallographic aspects as well as some interesting notes regarding the repetitive nitriding of bridge dies.

GREAT progress has been made in recent years in both fields of aircraft design and manufacture. No longer is the designer completely in the dark regarding the operational loads his aircraft will have to sustain, nor completely ignorant of the capabilities of its structure. Progress has brought knowledge of the sort of operational load likely to be encountered in both flight and landing operations as well as powerful methods of analysis of aircraft structures. Even that, however, is not enough, for without a thorough understanding of the possibilities and properties of the materials at the designer's command, he cannot hope to utilize such knowledge to the full.

The purpose of this paper is to find an efficient way by using finite volume method (FVM) to simulate the aluminum alloy profile extrusion processes.

By assuming isotropic conditions, the hot aluminum material is described as a non‐linear Newtonian fluid material. Semi‐implicit method for pressure‐linked equations algorithm is used to calculate the physical fields, and the dynamic viscosity is updated then. Volume of fluid method and moving grid method are also used for unsteady flow to catch the free surface of the material and the moving bound.

FVM model in this paper is an accurate and efficient method for the numerical simulation of aluminum profile extrusion processes. Compared with finite element method software, FVM model is both memory and CPU efficient.

Provide theoretical reference for sound extrusion process and die designs, which are the key factors to produce desirable products in industrial production.

The paper finds an efficient way to introduce the FVM in computational fluid dynamics field into the simulation of the steady and unsteady aluminum alloy profile extrusion processes. It provides a reference for people who are interested in FVM and extrusion processes.

Fused Filament Fabrication (FFF) is an extrusion-based manufacturing process using fused thermoplastics. Despite its low cost, the FFF is not extensively used in high-value industrial sectors mainly due to parts' anisotropy (related to the deposition strategy) and residual stresses (caused by successive heating cycles). Thus, this study aims to investigate the process improvement and the optimization of the printed parts.

In this work, a meshless technique – the Radial Point Interpolation Method (RPIM) – is used to numerically simulate the viscoplastic extrusion process – the initial phase of the FFF. Unlike the FEM, in meshless methods, there is no pre-established relationship between the nodes so the nodal mesh will not face mesh distortions and the discretization can easily be modified by adding or removing nodes from the initial nodal mesh. The accuracy of the obtained results highlights the importance of using meshless techniques in this field.

Meshless methods show particular relevance in this topic since the nodes can be distributed to match the layer-by-layer growing condition of the printing process.

Using the flow formulation combined with the heat transfer formulation presented here for the first time within an in-house RPIM code, an algorithm is proposed, implemented and validated for benchmark examples.

Limited volume lubrication as applied in metal working operations has grown significantly in the South African manufacturing industry over the past years. The need for a cleaner factory environment and the international competition faced by local producers, necessitated a re‐evaluation of the efficiency of operations pertaining to tool life and quality of products. The technique started with sawing of aluminium and was extended through copper and stainless steel to mild steel manufacturing operations including band sawing, drilling and tapping, pressing and hot forging. The technique is limited by the material to be worked as well as the rate of metal working. Synthetic lubricants proved to be indispensable in meeting the challenges faced when applying the technique.

The purpose of this paper is to analyse and improve the temperature uniformity of aluminium billets heated by superconducting DC induction heaters.

A 3D electromagnetic model coupled with a heat transfer model is developed to calculate the heating process of the billets which are rotated in uniform transverse DC magnetic field. A laboratory-scale DC induction heater prototype has been built to validate the model. The results from simulation and measurement have a good agreement. The model is used to investigate the factors affecting the temperature uniformity of aluminium billets.

The results from simulation show that lower rotation speeds always mean better temperature uniformity along the radial direction, due to the increase in power penetration. However, the situation is very different for the temperature distribution along the axial direction. When the rotation speed is low, the temperature at the ends is lower than other parts. The situation reverses as the rotation speeds increase. This phenomenon is referred to as the “ending effect” in this paper.

Because of the ending effect, a lower rotation speed does not always result in better overall temperature uniformity, especially for billets of smaller sizes.

There is an optimal rotation speed that yields the best overall temperature uniformity. Lower rotation speeds are not always preferred. The results and numerical model developed are very useful in the design of a superconducting DC induction heater.

The temperature uniformity of aluminium billets heated by DC induction heaters is investigated and optimized.