Production Processes and Characteristics of Porous Alumina with Air Bubbles Introduced into Slurry

2015 ◽  
Vol 656-657 ◽  
pp. 86-91 ◽  
Author(s):  
Akihiko Ikuta ◽  
Hideki Kyogoku ◽  
Hiroyuki Suzuki
Keyword(s):  
Production Process ◽  
Bending Strength ◽  
Porous Alumina ◽  
Slip Casting ◽  
Air Bubbles ◽  
Sintered Compact ◽  
Four Point Bending ◽  
Production Processes ◽  
Shaping Process ◽  
Observation Results

In this study, production processes for porous alumina, and the characteristics of the material, were investigated. Porous alumina was produced by a wet-shaping process in which air bubbles were introduced into the slurry. The feature of this production process is that many pores are produced by slip casting carried out using whipped slurry, where only the conditions of the slurry are adjusted. The advantage of this process is its simplicity. From the results, it is made clear that a green compact of porous alumina can be produced by changing the amount of solvent and binder, and also that a sintered compact of porous alumina can be produced by a low sintering temperature, such as 1473 K. The four point bending strength of porous alumina is about 515 MPa when the porosity is about 30 %. The excellent characteristics of the sintered compact of porous alumina are shown by the observation results of the fracture surface in this production process. The dense alumina body is sintered while maintaining the fine grains, and with the micro pores remaining in the grain boundary.

Production of Cemented Carbide-Alumina Composite Material by Wet-Shaping Process

2017 ◽  
Vol 749 ◽  
pp. 199-204
Author(s):  
Akihiko Ikuta ◽  
Hideki Kyogoku ◽  
Hiroyuki Suzuki
Keyword(s):  
Composite Material ◽  
Production Process ◽  
Filler Metal ◽  
Fine Powder ◽  
Cemented Carbide ◽  
Sintered Compact ◽  
Shaping Process ◽  
Alumina Composite ◽  
Sintering Conditions ◽  
Sintering Characteristics

In this study, the characteristics of the production process of cemented carbide-alumina composite material made using the wet-shaping process were investigated. The production process in this study produced a green compact of composite material by repeating the wet-shaping process for the molding of each material, and it made possible the sintering of plural materials with varying sintering conditions at the same time, a process that was difficult until now. By using wet-shaping and ultra-fine powder, which have superior sintering characteristics, sintering conditions were found in which it was possible to sinter cemented carbide and alumina at the same time, with a sintering temperature of 1723 K and a sintering time of 5.4 ks. With these sintering conditions, the relative densities of the sintered compact of cemented carbide and alumina were 99.0 % and 98.9 %, respectively. It is clear that the characteristics of sintered compact made with these sintering conditions are superior. When the cemented carbide slurry and the alumina slurry were layered by repeating the wet-shaping process, a composite material was able to be produced by inserting an active brazing filler metal in the interface to improve the bondability of the cemented carbide and the alumina during the sintering. However, it was observed that the active brazing filler metal and the cobalt in the cemented carbide flowed out from the interface between the cemented carbide and the alumina in the sintered compact of the composite material.

The Preparation and Properties of Functionally Graded Alumina/Zirconia-Toughened Alumina (ZTA) Ceramics for Biomedical Applications

2005 ◽  
Vol 290 ◽  
pp. 348-352 ◽  
Author(s):  
Sabina Beranič Klopčič ◽  
Saša Novak ◽  
Tomaž Kosmač ◽  
H.G. Richter ◽  
S. Hecht-Mijic
Keyword(s):  
Biomedical Applications ◽  
Mechanical Performance ◽  
Slip Casting ◽  
Functionally Graded ◽  
Air Bubbles ◽  
Layered Composites ◽  
Casting Technique ◽  
Ph Values ◽  
Shaping Process ◽  
Zirconia Toughened Alumina

Functionally graded alumina/zirconia-toughened alumina (ZTA) ceramics for biomedical applications were designed with a hard, wear-resistant alumina surface and a tough, zirconia-rich core. The main goal was to achieve an improved mechanical performance by introducing a residual compressive stress in the outer surfaces. Symmetrical, 7-layered samples were prepared by the sequential slip-casting of specimens from suspensions prepared at the inherent pH values, close to the pH values at which the maximum (negative) zetapotential was measured. No sintering or tunneling cracks were observed in the samples, but large defects, such as big agglomerates, air bubbles and large circular pores at layer interfaces, which resulted from preparing the samples using the slip-casting technique, were readily observed. The strength of the symmetrical composites is influenced by the presence of defects, which most probably originate from the shaping process. Therefore, the defects have to be regarded as the reason why the strength of the 7-layered composites is low.

scholarly journals Application of the Deep CNN-Based Method in Industrial System for Wire Marking Identification

Energies ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3659
Author(s):  
Andrzej Szajna ◽  
Mariusz Kostrzewski ◽  
Krzysztof Ciebiera ◽  
Roman Stryjski ◽  
Waldemar Woźniak
Keyword(s):  
Production Process ◽  
Process Development ◽  
Process Time ◽  
Industrial System ◽  
Assembly Process ◽  
Production Environment ◽  
Deep Convolutional Neural Networks ◽  
Control Cabinet ◽  
Production Processes ◽  
The Wire

Industry 4.0, a term invented by Wolfgang Wahlster in Germany, is celebrating its 10th anniversary in 2021. Still, the digitalization of the production environment is one of the hottest topics in the computer science departments at universities and companies. Optimization of production processes or redefinition of the production concepts is meaningful in light of the current industrial and research agendas. Both the mentioned optimization and redefinition are considered in numerous subtopics and technologies. One of the most significant topics in these areas is the newest findings and applications of artificial intelligence (AI)—machine learning (ML) and deep convolutional neural networks (DCNNs). The authors invented a method and device that supports the wiring assembly in the control cabinet production process, namely, the Wire Label Reader (WLR) industrial system. The implementation of this device was a big technical challenge. It required very advanced IT technologies, ML, image recognition, and DCNN as well. This paper focuses on an in-depth description of the underlying methodology of this device, its construction, and foremostly, the assembly industrial processes, through which this device is implemented. It was significant for the authors to validate the usability of the device within mentioned production processes and to express both advantages and challenges connected to such assembly process development. The authors noted that in-depth studies connected to the effects of AI applications in the presented area are sparse. Further, the idea of the WLR device is presented while also including results of DCNN training (with recognition results of 99.7% although challenging conditions), the device implementation in the wire assembly production process, and its users’ opinions. The authors have analyzed how the WLR affects assembly process time and energy consumption, and accordingly, the advantages and challenges of the device. Among the most impressive results of the WLR implementation in the assembly process one can be mentioned—the device ensures significant process time reduction regardless of the number of characters printed on a wire.

Characteristics of Low Temperature Degradation Free ZTA for Artificial Joint

2014 ◽  
Vol 631 ◽  
pp. 18-22 ◽  
Author(s):  
Junji Ikeda ◽  
Takayuki Murakami ◽  
Takayoshi Shimozono ◽  
Reiji Watanabe ◽  
Mikio Iwamoto ◽  
...  
Keyword(s):  
Low Temperature ◽  
Phase Stability ◽  
Mechanical Characteristics ◽  
Bending Strength ◽  
Accelerated Aging ◽  
Ceramic Materials ◽  
Wear Property ◽  
Artificial Joint ◽  
Four Point Bending ◽  
Bearing Materials

Low temperature degradation free Zirconia toughened alumina (ZTA) has been developed. It is reported that ZTA has higher mechanical strength compared to alumina due to the stress induced transformation and spontaneously transformation of zirconia phase on some ZTA have been occurred. For achieving the higher reliability of artificial joint prosthesis alternative to alumina and other ceramic materials, it is necessary to improve and validate the both mechanical characteristics and phase stability at the same time. We evaluated that microstructure, mechanical characteristics and phase stability of newly developed ZTA (BIOCERAM®AZUL). It was confirmed that four-point bending strength and weibull modulus were extreamly high, and ZTA has higher reliability. There were no significant changes and deterioration in four-point bending strength, crystal structure and wear property with and without accelerated aging test. Newly developed ZTA not only with high mechanical characteristics but also with phase stability could be quite useful as bearing materials in artificial joints for longer clinical use.

Research on Damage and Bending Properties of AZ31 Magnesium Alloy

2012 ◽  
Vol 184-185 ◽  
pp. 1163-1166
Author(s):  
Xi An Xie ◽  
Gao Feng Quan
Keyword(s):  
Magnesium Alloy ◽  
Applied Load ◽  
Bending Strength ◽  
Az31 Magnesium Alloy ◽  
Bending Test ◽  
Bending Properties ◽  
Four Point Bending ◽  
Heat Treated ◽  
Four Point Bending Test ◽  
Initial Cracks

Through the four-point bending test of lath-shaped heat treated AZ31 magnesium alloy, the bending properties and damage characteristics were explored. The results show that the optimal bending strength of the magnesium alloy were 355.1MPa and 259.2MPa for extruded and cast samples, respectively, after corresponding heat treatment with 350°C, 90min and 400°C, 30min. The initial cracks both occurred at the loading point after applied load exceeded the yield limit of AZ31 magnesium alloy. Surface bump, cracks and other damage morphology accompanied by a large number of twinning organizations were found on the surface of the samples.

Microworld Development

2008 ◽  
Vol 40 (1) ◽  
pp. 84-97 ◽  
Author(s):  
Mathias M. Fischer ◽  
Federico Barnabè
Keyword(s):  
Production Process ◽  
Model Building ◽  
Calcium Carbide ◽  
Group Model ◽  
Interactive Learning Environment ◽  
Industrial Firms ◽  
Chemical Company ◽  
Production Processes ◽  
Computer Based ◽  
Building Project

The article presents the outcomes of a group model-building project at a chemical company that produces calcium carbide. The project led not only to the creation of a system dynamics model describing the production process but also to a microworld, a computer-based interactive learning environment meant to reproduce most of the features of the operating and controlling software actually used in the company. The process of organizational learning, the gaining of a better common understanding of the production process, and the development of the different mental models of the plant operators were some of the project's main goals. Moreover, the method followed during the project can be considered as general and can be used mainly in a variety of production processes in most manufacturing industrial firms both for the modeling of production processes and for teaching and training the operators who manage such systems.

scholarly journals The stability of major and trace element concentrations from musts to Champagne during the production process

OENO One ◽  
2022 ◽  
Vol 56 (1) ◽  
pp. 29-40
Author(s):  
Robin Cellier ◽  
Sylvain Berail ◽  
Ekaterina Epova ◽  
Julien Barre ◽  
Fanny Claverie ◽  
...  
Keyword(s):  
Trace Elements ◽  
Production Process ◽  
Trace Element ◽  
Narrow Range ◽  
Grape Juice ◽  
Elemental Concentrations ◽  
Element Concentrations ◽  
Production Processes ◽  
Overall Stability ◽  
The Stability

Thirty-nine Champagnes from six different brands originating from the AOC Champagne area were analyzed for major and trace element concentrations in the context of their production processes and in relation to their geographical origins. Inorganic analyses were performed on the must (i.e., grape juice) originating from different AOC areas and the final Champagne. The observed elemental concentrations displayed a very narrow range of variability. Typical concentrations observed in Champagne are expressed in mg/L for elements such as K, Ca, Mg, Na, B, Fe, A, and Mn. They are expressed in µg/L for trace elements such as Sr, Rb, Ba, Cu, Ni, Pb Cr and Li in decreasing order of concentrations. This overall homogeneity was observed for Sr and Rb in particular, which showed a very narrow range of concentrations (150 < Rb < 300 µg/L and 150 < Sr < 350 µg/L) in Champagne. The musts contained similar levels of concentration but showed slightly higher variability since they are directly influenced by the bedrock, which is quite homogenous in the AOC area being studied. Besides the homogeneity of the bedrock, the overall stability of the concentrations recorded in the samples can also be directly linked to the successive blending steps, both at the must level and prior to the final bottling. A detailed analysis of the main additives, sugar, yeast and bentonite, during the Champagne production process, did not show a major impact on the elemental signature of Champagne.

Developing and Using an Expert System for Planning the Production of Structural Piece-Parts

1992 ◽  
Vol 8 (03) ◽  
pp. 163-183
Author(s):  
Mark Spicknall
Keyword(s):  
Expert System ◽  
Expert Systems ◽  
Production Process ◽  
Production Facility ◽  
Inference Process ◽  
Expert System Shell ◽  
Production Processes ◽  
Potential Applications ◽  
Part Production

This paper presents an example of how expert systems can be developed and used for planning structural piece-part production. First, expert systems are briefly and generically described. Then the production processes within a shipyard-like structural piece-part production facility are defined within an expert system "shell"; that is, the "objects," "attributes," and "rules" describing the production process are established and explained. Then various structural piece-parts are described to the system and the system identifies the required production processes for each described part. The inference process underlying the identification of these processes is described for each of these parts. Finally, potential applications of expert systems to other areas of shipbuilding operations are discussed.

Fracture Mechanics of Y2O3 Ceramics at High Temperatures

2014 ◽  
Vol 89 ◽  
pp. 88-93
Author(s):  
Marek Boniecki ◽  
Zdzislaw Librant ◽  
Władysław Wesołowski ◽  
Magdalena Gizowska ◽  
Marcin Osuchowski ◽  
...  
Keyword(s):  
Fracture Toughness ◽  
Grain Size ◽  
High Temperature ◽  
Fracture Mechanics ◽  
High Purity ◽  
Room Temperature ◽  
Bending Strength ◽  
Hot Isostatic Pressing ◽  
Temperature Changes ◽  
Four Point Bending

Fracture toughness KIc and four-point bending strength σc at high temperature (up to 1500 °C) of Y2O3 ceramics of various grain size were measured. The ceramics were prepared by pressureless air sintering and next hot isostatic pressing of high purity (99.99%) Y2O3 powder. Relative density of about 99 % was achieved. Photos of microstructures revealed small pores distributed mainly inside grains. For smallest grain size (2 - 9 μm) ceramics KIc and σc are almost constant from 20 ° to 1200 °C and next they decrease. For biggest grain size (about 44 μm) they increase up to 800 °C and next they keep constant up to 1200 °C. The micrographs analyses of fracture surfaces indicated that transgranular mode of fracture at room temperature changes to almost intergranular at higher temperatures.

Research on Underground Coal Mine Production Process Analysis and Informatization

2010 ◽  
Vol 171-172 ◽  
pp. 278-282 ◽  
Author(s):  
Jin Feng Wang ◽  
Li Jie Feng ◽  
Zhen Zhao ◽  
Hua Jie Yu
Keyword(s):  
Information System ◽  
Production Process ◽  
Coal Mine ◽  
Process Analysis ◽  
Underground Coal Mine ◽  
Continuous Type ◽  
Production Processes ◽  
Mine Production ◽  
Discrete Type

This article analyzes the characteristics of underground coal mine production process, and compares underground coal mine production process with discrete type and continuous type production processes. On this basis, it investigates the construction and implementation countermeasures on underground coal mine information system.

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