Forming Processes of Modern Metallic Materials

Additive manufacturing technology is one of the main components of the fourth industrial revolution known as Industry 4.0. Over the last decades, the increase in the dynamics of the development of this technology manifests itself in the form of a wide spectrum of implementations of the methods in the production processes of many elements. This paper presents the latest achievements in the production of gears where the additive technologies have been applied with the use of polymers and metallic materials. The most frequently used methods in this field were indicated, as well as problems related to geometric accuracy or fatigue life of elements manufactured with the use of the methods mentioned. In addition, future directions of gear design, the implementation of which was possible thanks to the use of AM, as well as the scope of research that should be undertaken in this area in the future, were defined. Keywords: mechanical engineering, manufacturing technologies, additive manufacturing, gears

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High Entropy Alloys Manufactured by Additive Manufacturing

Metals ◽

10.3390/met10050639 ◽

2020 ◽

Vol 10 (5) ◽

pp. 639 ◽

Cited By ~ 4

Author(s):

José M. Torralba ◽

Mónica Campos

Keyword(s):

Additive Manufacturing ◽

Review Paper ◽

Physical Metallurgy ◽

High Entropy Alloys ◽

Metallic Materials ◽

Processing Conditions ◽

High Entropy ◽

New Material ◽

Manufacturing Technologies ◽

Structure And Microstructure

High entropy alloys have attracted much interest over the last 16 years due to their promising an unusual properties in different fields that offer many new possible application. Additionally, additive manufacturing has drawn attention due to its versatility and flexibility ahead of a new material challenge, being a suitable technology for the development of metallic materials. Moreover, high entropy alloys have demonstrated that many gaps exist in the literature on its physical metallurgy, and in this sense, additive manufacturing could be a feasible technology for solving many of these challenges. In this review paper the newest literature on this topic is condensed into three different aspects: the different additive manufacturing technologies employed to process high entropy alloys, the influence of the processing conditions and composition on the expected structure and microstructure and information about the mechanical and corrosion behavior of these alloys.

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AHP method to determine the optimal technological variant for maxillofacial implant fabrication

MATEC Web of Conferences ◽

10.1051/matecconf/201817803012 ◽

2018 ◽

Vol 178 ◽

pp. 03012

Author(s):

Luciana Laura Dincă ◽

Alexandra Banu ◽

Aurelian Vişan ◽

Nicolae Ionescu

Keyword(s):

Additive Manufacturing ◽

Mechanical Strength ◽

Technological Process ◽

Clinical Case ◽

Metallic Materials ◽

Optimal Process ◽

Ahp Method ◽

Materials Used ◽

Manufacturing Technologies ◽

The Right

The paper describes different technologies for manufacturing maxillofacial implant. By using the AHP method the AM, the direct manufacturing technology SLM is the optimal process. Technological variants for obtaining a maxillofacial implant that replaces the right zygomatic bone and a part of maxilla, based on a real clinical case are presented. Starting from the possibility of processing the biocompatible metallic materials used in the oral and maxillofacial technique, it is possible to classify the technological process variants in procedures that use and do not use additive manufacturing technologies. The aim of this paper is to show how important it is to select the optimal technological process in obtaining a maxillofacial implant. It has been analyzed the technological processes of achieving the maxillofacial implant, both those which use the additive manufacturing technologies and those which do not use such technologies, highlighting not only the benefits but also their limits. Based on criteria such as: mechanical strength, porosity, roughness, accuracy, anchorage, time and cost, by using the AHP method, it is possible to choose the optimal technological process for achieving the maxillofacial implant.

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SEM Examination of a Used Diamond Knife

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100066310 ◽

1971 ◽

Vol 29 ◽

pp. 452-453

Author(s):

J. Temple Black

Keyword(s):

Electron Microscope ◽

High Voltage ◽

High Magnification ◽

Metallic Materials ◽

Wide Spread ◽

Thin Sections ◽

Transmission Electron ◽

Scanning Transmission ◽

Scanning Electron ◽

Diamond Knife

Since its introduction by Fernandez-Moran, the diamond knife has gained wide spread usage as a common material for cutting of thin sections of biological and metallic materials into thin films for examination in the transmission electron microscope. With the development of high voltage E.M. and scanning transmission E.M., microtomy applications will become increasingly important in the preparation of specimens. For those who can afford it, the diamond knife will thus continue to be an important tool to accomplish this effort until a cheaper but equally strong and sharp tool is found to replace the diamond, glass not withstanding.In Figs. 1 thru 3, a first attempt was made to examine the edge of a used (β=45°) diamond knife by means of the scanning electron microscope. Because diamond is conductive, first examination was tried without any coating of the diamond. However, the contamination at the edge caused severe charging during imaging. Next, a thin layer of carbon was deposited but charging was still extensive at high magnification - high voltage settings. Finally, the knife was given a light coating of gold-palladium which eliminated the charging and allowed high magnification micrographs to be made with reasonable resolution.

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Observation of secondary slip systems in tungsten bicrystals

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100112361 ◽

1984 ◽

Vol 42 ◽

pp. 478-479

Author(s):

J. R. Fekete ◽

R. Gibala

Keyword(s):

Stress Field ◽

Grain Boundaries ◽

Deformation Behavior ◽

Stress Axis ◽

Polycrystalline Materials ◽

Slip Systems ◽

Metallic Materials ◽

Twist Boundary ◽

Secondary Slip ◽

Plane Normal

The deformation behavior of metallic materials is modified by the presence of grain boundaries. When polycrystalline materials are deformed, additional stresses over and above those externally imposed on the material are induced. These stresses result from the constraint of the grain boundaries on the deformation of incompatible grains. This incompatibility can be elastic or plastic in nature. One of the mechanisms by which these stresses can be relieved is the activation of secondary slip systems. Secondary slip systems have been shown to relieve elastic and plastic compatibility stresses. The deformation of tungsten bicrystals is interesting, due to the elastic isotropy of the material, which implies that the entire compatibility stress field will exist due to plastic incompatibility. The work described here shows TEM observations of the activation of secondary slip in tungsten bicrystals with a [110] twist boundary oriented with the plane normal parallel to the stress axis.

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