This paper gives a review of the finite element techniques (FE)applied in the area of material processing. The latest trends in metalforming, non‐metal forming and powder…
Abstract
This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming and powder metallurgy are briefly discussed. The range of applications of finite elements on the subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for the last five years, and more than 1100 references are listed.
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N. Takahashi, S. Nakazaki, H. Kato and J. Asaumi
The purpose of this paper is to provide an approach to the optimal design of open type magnetic circuit of permanent magnet having uniform field.
Abstract
Purpose
The purpose of this paper is to provide an approach to the optimal design of open type magnetic circuit of permanent magnet having uniform field.
Design/methodology/approach
The Biot‐Savart's law and evolution strategy are used for the design of permanent magnet configuration. The optimization is carried out by changing the objective function, dimension of target region, and target flux density.
Findings
The obtained uniformity is affected by the selection of objective function, dimension of target region, and target flux density. About 50 ppm uniformity of 0.08 T in the imaging area is obtained by changing the dimensions, dimension of target region, and target flux of 3D magnets and the amplitudes of magnetization and the directions of magnetization vectors.
Originality/value
This paper describes a new approach for obtaining the optimal shape of open type magnetic circuit which may be used when magnetic resonance imaging is carried out.
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A wire matrix has been developed for mounting LED dot matrix displays whereby insulated wires are ‘woven’ to produce a matrix that is fixed on an aluminium board with epoxy…
Abstract
A wire matrix has been developed for mounting LED dot matrix displays whereby insulated wires are ‘woven’ to produce a matrix that is fixed on an aluminium board with epoxy adhesive. This monolayer woven wire board simplifies the fabrication process of the display board while at the same time showing more than double the heat dissipation of conventional insulated aluminium printed circuit boards and five times that of conventional glass epoxy printed circuit boards when mounted with bare LED chips. In addition, it is suitable for high‐density and high‐brightness LED dot matrix displays.
A surface‐mount in‐line light emitting diode (LED) array was developed for mounting an LED dot matrix display on a single‐sided insulated metal substrate (IMS). This LED array has…
Abstract
A surface‐mount in‐line light emitting diode (LED) array was developed for mounting an LED dot matrix display on a single‐sided insulated metal substrate (IMS). This LED array has heat dissipating cathode leads and an anode lead that works as a jumper wire. Good heat dissipation of the LED array was obtained on an aluminium IMS.
William Kline, Masaaki Kotabe, Robert Hamilton and Stanley Ridgley
The purpose of this paper is to provide insights from the upper echelon, agency, and organizational identification literatures to help explain cross-cultural differences in top…
Abstract
Purpose
The purpose of this paper is to provide insights from the upper echelon, agency, and organizational identification literatures to help explain cross-cultural differences in top management team pay.
Design/methodology/approach
This is a theoretical paper building upon the executive compensation literature examining US and Japanese pay schemes.
Findings
The paper presents three propositions relating to the influence of organizational constitution and organizational identification on the level of pay, as well as the allocation of pay in top management team compensation schemes.
Originality/value
There is relatively little research focusing on why there are cross-cultural pay differences. This paper uses US and Japanese studies to highlight mechanisms that can foster principal-agent goal alignment in different contexts.
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Crislaine da Cruz, Ivan Mathias, Mariza Veiga Senk, Gelson Biscaia de Souza and Francisco Carlos Serbena
Lithium disilicate glass-ceramics (LS2 GC) are widely used as dental prosthetics and dental restorations. Based LS2 GC have hardness and translucency similar to that of natural…
Abstract
Purpose
Lithium disilicate glass-ceramics (LS2 GC) are widely used as dental prosthetics and dental restorations. Based LS2 GC have hardness and translucency similar to that of natural teeth. This study aims to investigate the tribological features of LS2 GC with crystalline volume fraction of 64% and different crystal sizes from 8 µm to 34 µm for different counterparts.
Design/methodology/approach
The tribological behavior was investigated using a pin-on-disc tribometer with alumina and tungsten carbide (WC) spheres, applied load of 5 N and sliding speed of 5 cm/s at normal conditions. The coefficient of friction was measured continuously up to 10,000 sliding cycles. The specific wear rate was calculated from tribological and profile measurements. The wear mechanism was investigated by surface morphology analysis.
Findings
The coefficient of friction during running-in varied from 0.8 to 1.0 for the alumina counterpart, because of severe wear. Afterwards, it reduced and reached a stationary regime, characterized by a mild wear regime and the formation of a tribolayer formed by the debris. For the WC counterpart, the coefficient of friction curves increased initially with sliding cycles up to a stationary regime. The samples tested against WC presented the lowest specific wear rate (k), and no variation of wear rate with crystal size was observed. For samples tested against the alumina, crystallization and crystal size increased the wear resistance.
Originality/value
This study evaluated the effect of different counterfaces on the tribological properties of the LS2 GC, an important glass-ceramic base for many dental prosthetics and dental restorations, discussing results in light of the contact mechanics. Different specific wear rates, wear regimes and dependence on the glass-ceramic microstructure were observed depending on the counterpart.
Peer review
The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2019-0352/
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Ioan Doroftei and Yvan Baudoin
At present, more than 100 million undetonated landmines left over from wars remain buried worldwide. These mines kill or injure approximately 3,000 individuals each year (80…
Abstract
Purpose
At present, more than 100 million undetonated landmines left over from wars remain buried worldwide. These mines kill or injure approximately 3,000 individuals each year (80 persons per day), most of them civilians. They represent a particularly acute problem in developing countries and nations already economically hard hit by war. The problem of unexploded mines has become a serious international issue, with many people striving to find a solution. The purpose of this paper is to examine the requirements of the robotic systems for humanitarian demining purposes. It will discuss a hexapod walking robot developed at the Royal Military Academy of Brussels in collaboration with the Free University of Brussels, Belgium, in the framework of the Humanitarian Demining Project (HUDEM).
Design/methodology/approach
Considerations for the design of the walking robot according to the humanitarian demining requirements are discussed in detail.
Findings
A successful walking robot design for demining purposes must consider functional requirements relevant to this difficult application. The principal requirements are mentioned in this paper.
Originality/value
This paper is the result of the research of the HUDEM project team and it is of value to engineers and researchers developing robotic systems for humanitarian demining purposes.
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Na Fan, Liqiang Chai, Peng Wang and Jun Liang
This paper aims to study the tribocorrosion behavior of 304 stainless steel (SS) sliding against SiC and Si3N4 counterparts in artificial seawater.
Abstract
Purpose
This paper aims to study the tribocorrosion behavior of 304 stainless steel (SS) sliding against SiC and Si3N4 counterparts in artificial seawater.
Design/methodology/approach
The tribocorrosion behavior of 304SS sliding against SiC and Si3N4 balls in artificial seawater has been investigated. The tests were conducted using a ball-on-disk rig equipped with an electrochemical workstation. The friction coefficient, surface morphology, wear volume and current density were determined.
Findings
When 304SS sliding against SiC ball, a smooth surface with a silica layer was formed on the top, which led to the low friction coefficient, current density and small wear volume. For 304SS-Si3N4 tribo-pair, a lot of metal debris was scattered on contact surfaces leading to high friction coefficient, current density and big wear volume.
Research limitations/implications
This research suggests that the lubrication effect of silicon-based ceramics is related to counterpart specimen in artificial seawater.
Practical implications
The results may help us to choose the appropriate ceramic ball under seawater environment.
Originality/value
The main originality of the work is to reveal the tribocorrosion behavior of 304SS sliding against SiC and Si3N4 balls, which help us to realize that the Si3N4 ball as water-lubricated ceramics could not exhibit lubrication effect when coupled with 304SS in artificial seawater.