Selection of Nanostructured Zirconium Dioxide Crystals under Dry Friction against Molybdenum

2022 ◽  
Vol 1049 ◽  
pp. 158-164
Author(s):  
Valery V. Alisin
Keyword(s):  
Mechanical Properties ◽  
Dry Friction ◽  
Zirconium Dioxide ◽  
Friction Couple ◽  
Molybdenum Coating ◽  
Friction Units ◽  
Antifriction Properties ◽  
Hydraulic Equipment ◽  
Scoring Resistance ◽  
Selection Of

The article considers the issues of contact interaction of nanostructured zirconium dioxide crystals with molybdenum coating on titanium-based alloy ВТ9. The following statement is substantiated: the best mechanical properties of crystals correspond to the total amount of 2.8% additives of stabilizing and doping rare earths elements. Antifriction properties of crystals under dry friction against molybdenum are investigated. Tribological testing was performed on a reciprocating friction gauge simulating the operation of a plunger in a cylinder. The high scoring resistance of the friction couple under study was experimentally proved; the friction coefficient did not exceed 0.07. On the basis of the study performed, the friction couple is defined as promising for increasing the lifetime and reliability of friction units for hydraulic equipment and fuel pumps.

scholarly journals Tribological Properties of Sapphire under Dry Friction against Chromium and Zirconium Ceramics

2022 ◽  
Author(s):  
V. Alisin
Keyword(s):  
Mechanical Properties ◽  
Modulus Of Elasticity ◽  
Dry Friction ◽  
Friction And Wear ◽  
Open Space ◽  
Frictional Contact ◽  
Friction Couple ◽  
Vickers Indent ◽  
Friction Units ◽  
Zirconium Ceramics

Abstract. The issues of sapphire friction and wear in contact with chrome steel and zirconium ceramics are discussed in this article. The kinetic microindentation method is used to study the mechanical properties of sapphire in frictional contact in modelling experiments on the indentation of a Vickers indent. Taking into account the anisotropy of the mechanical properties of sapphire, the influence of the load and orientation of the indent on the modulus of elasticity and hardness is analyzed. It has been established that, under dry friction conditions it is promising the use of zirconium ceramics in the supports of devices operating under conditions in which the use of lubricants is impossible. The possibility of using a friction couple of sapphire-zirconium ceramics in friction units operating in open space is noted.

scholarly journals Problem of Selection of Lubricants for ethelene High-Pressure Compressors. 2.Characteristic of object of investigation (review)

2018 ◽  
Vol 19 (4) ◽  
pp. 345-351
Author(s):  
H.O. Sirenko ◽  
M.I. Martynyuk ◽  
V.P. Svidersky ◽  
N.V. Shmaltser ◽  
O.V. Kuzyshyn
Keyword(s):  
Mechanical Properties ◽  
High Pressure ◽  
Practical Interest ◽  
Antifriction Properties ◽  
Different Content ◽  
Selection Of

Technology of obtaining and properties of ethylene compositions with different content of oils inside are researched. The antifriction properties of naphtene and polyglicol oils have been studied. Polyethyleneglycol and polypropyleneglycol-products of condensation accordingly of ethyleneglycol and propyleneglycol have today the practical interest as lubricants. It is shown viscous-mechanical properties of polyethylene during addition of different amount of lubricants.

scholarly journals Tsirkonievye keramicheskie materialy tribotekhnicheskogo naznacheniia

2019 ◽  
pp. 5-16
Author(s):  
Valerii Vasilevich Alisin
Keyword(s):  
Experimental Data ◽  
Service Life ◽  
High Temperatures ◽  
Zirconium Dioxide ◽  
Ceramic Materials ◽  
Operating Conditions ◽  
Optimal Selection ◽  
Friction Units ◽  
Tribotechnical Properties ◽  
Selection Of

The problem of improving the reliability and service life of friction units operating in extreme operating conditions, especially at high temperatures, is mainly solved by the use of ceramic materials. The paper analyzes the tribotechnical properties of ceramic materials based on partially stabilized zirconium dioxide and formulates proposals for the optimal selection of friction pairs based on experimental data.

Elaboration and Characterization of the Properties of Refractory Cr Base Alloys

2010 ◽  
Vol 72 ◽  
pp. 46-52 ◽  
Author(s):  
Laurent Royer ◽  
Stéphane Mathieu ◽  
Christophe Liebaut ◽  
Pierre Steinmetz
Keyword(s):  
Mechanical Properties ◽  
Melting Point ◽  
Molten Glass ◽  
Energy Production ◽  
Creep Properties ◽  
Refractory Alloys ◽  
Industrial Use ◽  
Kinetics Of ◽  
Selection Of

For energy production and also for the glass industry, finding new refractory alloys which could permit to increase the process temperatures to 1200°C or more is a permanent challenge. Chromium base alloys can be good candidates, considering the melting point of Cr itself, and also its low corrosion rate in molten glass. Two families of alloys have been studied for this purpose, Cr-Mo-W and Cr-Ta-X alloys (X= Mo, Si..). A finer selection of compositions has been done, to optimize their chemical and mechanical properties. Kinetics of HT oxidation by air, of corrosion by molten glass and also creep properties of several alloys have been measured up to 1250°C. The results obtained with the best alloys (Cr-Ta base) give positive indications as regards the possibility of their industrial use.

scholarly journals Advances in Fabricating the Electrospun Biopolymer-Based Biomaterials

2021 ◽  
Vol 12 (2) ◽  
pp. 26
Author(s):  
Sebastian Wilk ◽  
Aleksandra Benko
Keyword(s):  
Mechanical Properties ◽  
Whey Protein ◽  
Antimicrobial Properties ◽  
Protein Isolate ◽  
Review Article ◽  
Animal Tissues ◽  
Green Material ◽  
Good Potential ◽  
Fibrous Morphology ◽  
Selection Of

Biopolymers formed into a fibrous morphology through electrospinning are of increasing interest in the field of biomedicine due to their intrinsic biocompatibility and biodegradability and their ability to be biomimetic to various fibrous structures present in animal tissues. However, their mechanical properties are often unsatisfactory and their processing may be troublesome. Thus, extensive research interest is focused on improving these qualities. This review article presents the selection of the recent advances in techniques aimed to improve the electrospinnability of various biopolymers (polysaccharides, polynucleotides, peptides, and phospholipids). The electrospinning of single materials, and the variety of co-polymers, with and without additives, is covered. Additionally, various crosslinking strategies are presented. Examples of cytocompatibility, biocompatibility, and antimicrobial properties are analyzed. Special attention is given to whey protein isolate as an example of a novel, promising, green material with good potential in the field of biomedicine. This review ends with a brief summary and outlook for the biomedical applicability of electrospinnable biopolymers.

Mathematical Model of the Sintering Process of Iron-Copper Bearings

2007 ◽  
Vol 23 ◽  
pp. 119-122
Author(s):  
Cristina Teișanu ◽  
Stefan Gheorghe ◽  
Ion Ciupitu
Keyword(s):  
Experimental Data ◽  
Mechanical Properties ◽  
Mathematical Model ◽  
Regression Analysis ◽  
Function Optimization ◽  
Chemical Compositions ◽  
Sintering Process ◽  
Molybdenum Disulphide ◽  
Iron Copper ◽  
Antifriction Properties

The most important features of the self-lubricating bearings are the antifriction properties such as friction coefficient and wear resistence and some mechanical properties such as hardness, tensile strength and radial crushing strength. In order to improve these properties new antifriction materials based on iron-copper powders with several additional components (tin, lead and molybdenum disulphide) have been developed by PM techniques. To find the optimal relationship between chemical compositions, antifriction and mechanical properties, in this paper a mathematical model of the sintering process is developed, which highlighted the accordance of the model with data by regression analysis. For the statistical processing of the experimental data the VH5 hardness values of the studied materials were considered. The development of mathematical model includes the enunciation of the model, the establishment of the performance function (optimization) and the establishment of the model equations and verifying. The accordance of the model with experimental data has been highlighted by regression analysis

scholarly journals Mechanical properties of dental restorative materials: relative contribution of laboratory tests

2003 ◽  
Vol 11 (3) ◽  
pp. 162-167 ◽  
Author(s):  
Linda Wang ◽  
Paulo Henrique Perlatti D'Alpino ◽  
Lawrence Gonzaga Lopes ◽  
José Carlos Pereira
Keyword(s):  
Mechanical Properties ◽  
Laboratory Tests ◽  
Clinical Performance ◽  
Dental Materials ◽  
Correct Selection ◽  
Relative Contribution ◽  
Dental Restorative Materials ◽  
Restorative Materials ◽  
Dental Restorative ◽  
Selection Of

A wide variety of dental products that are launched on the market becomes the correct selection of these materials a difficult task. Although the mechanical properties do not necessarily represent their actual clinical performance, they are used to guide the effects of changes in their composition or processing on these properties. Also, these tests might help somehow the clinician to choose once comparisons between former formulations and new ones, as well as, with the leading brand, are highlighted by manufactures. This paper presents a review of the most important laboratory tests. In this manner, the knowledge of these tests will provide a critical opinion related to the properties of different dental materials.

scholarly journals The impact of the health condition of oaks from the Krotoszyn Plateau on the mechanical properties of timber structures

2015 ◽  
Vol 57 (4) ◽  
pp. 224-232
Author(s):  
Jarosław Siwiński ◽  
Katarzyna Kubiak ◽  
Miłosz Tkaczyk ◽  
Anna Mazur ◽  
Ryszard Rekucki
Keyword(s):  
Mechanical Properties ◽  
Health Condition ◽  
Health State ◽  
Timber Structures ◽  
Strength Parameters ◽  
Modified Method ◽  
Strength Tests ◽  
Prior Selection ◽  
The Impact ◽  
Selection Of

Abstract The study was conducted to perform a comparative analysis of the mechanical properties of wood samples derived from oaks in the Krotoszyn Plateau, which depend on the health state of the trees. Strength parameters of oak wood were calculated for selected diseased and healthy trees (according to the Roloff classification). The study was conducted by a modified method described in the standard Polish Norm PN EN 408+ A1: 2012. For testing, prior selection of wood samples showed that more wood samples of diseased trees compared with those of healthy oaks did not fulfil the Polish standard requirements. According to the method used, the average results of strength tests of timber structures from healthy oaks exhibited higher strength parameters than those of the diseased trees.

scholarly journals Influence of the Chemical Composition on Electrical Conductivity and Mechanical Properties of the Hypoeutectic Al-Si-Mg Alloys

2016 ◽  
Vol 61 (1) ◽  
pp. 353-360 ◽  
Author(s):  
B. Dybowski ◽  
J. Szymszal ◽  
Ł. Poloczek ◽  
A. Kiełbus
Keyword(s):  
Mechanical Properties ◽  
Electrical Conductivity ◽  
Chemical Composition ◽  
Aluminium Alloys ◽  
Mg Alloys ◽  
High Electrical Conductivity ◽  
Transportation Industry ◽  
Proper Selection ◽  
Ti Addition ◽  
Selection Of

Due to low density and good mechanical properties, aluminium alloys are widely applied in transportation industry. Moreover, they are characterized by the specific physical properties, such as high electrical conductivity. This led to application of the hypoeutectic Al-Si-Mg alloys in the power generation industry. Proper selection of the alloys chemical composition is an important stage in achievement of the demanded properties. The following paper presents results of the research on the influence of alloys chemical composition on their properties. It has been revealed that Si and Ti addition decreases electrical conductivity of the Al-Si-Mg alloys, while Na addition increases it. The mechanical properties of the investigated alloys are decreased by both silicon and iron presence. Sodium addition increases ductility of the Al-Si-Mg alloys.

General Method for Optimizing Composite Patch Repairs

2015 ◽  
Vol 1120-1121 ◽  
pp. 670-674
Author(s):  
Abdelmadjid Ait Yala ◽  
Abderrahmanne Akkouche
Keyword(s):  
Mechanical Properties ◽  
Stress Intensity Factor ◽  
Stress Intensity ◽  
Intensity Factor ◽  
Optimization Problem ◽  
Composite Patch ◽  
Matlab Program ◽  
Patch Repairs ◽  
Selection Of ◽  
General Method

The aim of this work is to define a general method for the optimization of composite patch repairing. Fracture mechanics theory shows that the stress intensity factor tends towards an asymptotic limit K∞.This limit is given by Rose’s formula and is a function of the thicknesses and mechanical properties of the cracked plate, the composite patch and the adhesive. The proposed approach consists in considering this limit as an objective function that needs to be minimized. In deed lowering this asymptote will reduce the values of the stress intensity factor hence optimize the repair. However to be effective this robust design must satisfy the stiffness ratio criteria. The resolution of this double objective optimization problem with Matlab program allowed us determine the appropriate geometric and mechanical properties that allow the optimum design; that is the selection of the adhesive, the patch and their respective thicknesses.

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