scholarly journals Improving the antifriction properties of the housing-rotor coupling in axial turbomachines

2021 ◽  
Vol 2094 (4) ◽  
pp. 042039
Author(s):  
V V Alisin
Keyword(s):  
Wear Resistance ◽  
Carbon Composite ◽  
High Wear Resistance ◽  
Gas Flows ◽  
High Speeds ◽  
Antifriction Properties ◽  
Carbon Composite Material ◽  
The Coefficient Of Friction ◽  
Very High ◽  
Thermal Stability Of

Abstract The article discusses the frictional interaction of carbon-carbon composite material on steel. Antifriction properties and wear resistance of the material under dry friction at speeds up to 100 m/s are investigated. The effect of velocity and contact pressure on the friction coefficient and wear resistance of a carbon composite is analyzed. The regularities of the change in the coefficient of friction are determined depending on the load-speed factors. The assumption is substantiated that the high thermal stability of the carbon composite, its low hardness, good antifriction properties and high wear resistance allow the material to be used in friction units operating at very high speeds and temperatures. In order to improve the reliability and reduce gas flows in axial turbomachines, on the basis of the study carried out, it is recommended that instead of heat-resistant coatings, a lining of the gas duct casing should be made of carbon composite.

YSS HAP72

Alloy Digest ◽  
2019 ◽  
Vol 68 (10) ◽  
Keyword(s):  
Wear Resistance ◽  
High Temperature ◽  
Powder Metallurgy ◽  
Tool Steel ◽  
High Speed ◽  
High Wear Resistance ◽  
Bend Strength ◽  
Temperature Performance ◽  
Very High

Abstract YSS HAP72 is a powder metallurgy high-speed tool steel with a very high wear resistance. This datasheet provides information on composition, hardness, and bend strength. It also includes information on high temperature performance. Filing Code: TS-779. Producer or source: Hitachi Metals America Ltd.

scholarly journals EPOXY ANTIFRICTION COATINGS FILLED WITH THE RICE HUSKS ASH TREATED WITH SURFACTANTS

2021 ◽  
pp. 28-36
Author(s):  
A. R. Valeeva ◽  
◽  
E. M. Gotlib ◽  
E. S. Yamaleeva ◽  
◽  
...  
Keyword(s):  
Wear Resistance ◽  
Rice Husk ◽  
Quaternary Ammonium ◽  
Bending Strength ◽  
Rice Husk Ash ◽  
Quaternary Ammonium Salts ◽  
Ammonium Salts ◽  
High Wear Resistance ◽  
Antifriction Coatings ◽  
Antifriction Properties

The use of epoxy antifriction coatings can significantly reduce thermal stress in the friction zone and expand the coating working temperature interval while keeping high wear resistance. The paper considers the effect of non-activated and activated by surfactants silicate filler – rice husk ash on the physicochemical and mechanical properties of epoxy materials applied as antifriction coatings. All studied samples of rice husk ash, both initial and activated with surfactants, have an alkaline surface nature. The study identified that all cationic quaternary ammonium salts (QAS) reduce the pH of rice husk ash. At the same time, nonionic OXIPAV increases this indicator. Activation of the rice husk ash surface, both by the quaternary ammonium salts and aminosilanes, significantly reduces the porosity of this silicate. In this case, the average pore diameter does not change significantly, and their specific surface area decreases significantly, to a lesser extent, when activated by nonionic quaternary ammonium salts. The application of quaternary ammonium salts and aminosilanes in the amount of 33 % for activation of the surface of the investigated silicate filler reduces its modifying effect in epoxy compositions, regardless of the chemical structure of the surfactants used, which is not a typical effect. Therefore, the authors assumed that the suboptimal concentration of quaternary ammonium salts and aminosilanes was used. The study identified that the optimal concentration of 50 % alcohol solution of KATAPAV is 14.7–21 %. In this range of the QAS content, there is a significant increase in hardness (about 40 %), a slight decrease in wear (about 10 %), and a significant decrease in the coefficient of static friction (up to 2 times). At the same time, the authors observed an increase in adhesion to metal up to 3 times and bending strength up to 25 %. Thus, rice husk ash activated with an optimal amount of quaternary ammonium salts is an effective modifier of epoxy coatings, which improves their antifriction properties and increases wear resistance, hardness, strength, and adhesion characteristics.

UDDEHOLM VANADIS 8 SUPERCLEAN

Alloy Digest ◽  
2020 ◽  
Vol 69 (11) ◽  
Keyword(s):  
Wear Resistance ◽  
Cold Work ◽  
Heat Treating ◽  
High Wear Resistance ◽  
High Carbon ◽  
Long Run ◽  
Powder Metallurgy Process ◽  
Cold Work Tool Steel ◽  
Metallurgy Process ◽  
Very High

Abstract Uddeholm Vanadis 8 SuperClean is a high-carbon, Cr-Mo-V, alloy cold work tool steel that is produced by the powder metallurgy process. It is suitable for very long run tooling where a combination of very high wear resistance and good chipping resistance is required. This datasheet provides information on composition, physical properties, hardness, and elasticity. It also includes information on heat treating and machining. Filing Code: TS-804. Producer or source: Uddeholms AB (a voestalpine company).

Modifying Wood for Creation Plain Bearings of Timber Machines

2020 ◽  
pp. 155-165
Author(s):  
G.A. Pilyushina ◽  
◽  
P.G. Pyrikov ◽  
E.A. Pamfilov ◽  
A.Ya. Danilyuk ◽  
...  
Keyword(s):  
Wear Resistance ◽  
Composite Materials ◽  
Sliding Friction ◽  
Three Dimensional ◽  
Design And Technology ◽  
High Wear Resistance ◽  
Problem Analysis ◽  
Metal Composite ◽  
Vibration Absorption ◽  
Antifriction Properties

The use of modified wood in different friction pairs of timber machines and processing equipment is largely due to its high wear resistance, low coefficient of friction and good dissipative characteristics. The positive properties of composite materials are achieved by using technologies of volumetric modification and implantation of antifriction and heatconducting elements, as well as by forming a composite of crushed wood with the addition of modifying additives and three-dimensional reinforcement. The expansion of the scope of using composite materials in the designs of units with sliding friction pairs necessitates carrying out research on their performance and formation conditions for high level tribotechnical parameters: wear resistance, antifriction, heat resistance, etc. Lack of information on the effect from the factors providing the functional characteristics of wood-based materials including thermal conductivity and vibration absorption significantly complicates the problem analysis in design and technology when developing and producing bearing joints. Therefore, the purpose of this work was studying the conditions of contact interaction of plain bearings made of wood-metal composite materials, allowing for rheological effects, and developing the ways of control their tribotechnical parameters by changing the structure, composition and phase filler. Models of bearings of different types, which allow creating a regulated stress-strain state in sleeves and liners, were developed for these purposes. Research of the bearings performance made it possible to find vibration-damping properties when using suspended crushed fractions in the composite. Increased antifriction properties are achieved in the process of wood modification with electrolytic copper, while the manufacturability of a bearing sleeve is achieved when the support is formed directly at the installation site. Unlike most of the used antifriction materials, the bushings wood maintains the stability of structure in conditions of volumetric compression at negative and positive temperatures, and the wear processes occurring on the contact surfaces of wood-metal bearings are followed by the compaction of the sleeve material. The subsequent destruction is predominantly of fatigue nature, initiated by the dynamics of vibrations and disturbances of the system; therefore, an important part of further research is the assessment of the relaxation ability of wood-metal composites under shock-vibration loading with optimization of their composition according to this criterion.

Machinability Assessment of Aluminium-Graphite-Silicon Carbide Hybrid Composites

2014 ◽  
Vol 894 ◽  
pp. 22-26 ◽  
Author(s):  
L. Krishnamurthy ◽  
G.L. Shekar ◽  
D. Abdul Budan ◽  
B.K. Sridhara
Keyword(s):  
Silicon Carbide ◽  
Wear Resistance ◽  
Hybrid Composites ◽  
Weight Ratio ◽  
Temperature Stability ◽  
Particulate Composites ◽  
High Wear Resistance ◽  
High Temperature Stability ◽  
Antifriction Properties ◽  
Silicon Carbide Particulate

Aluminium silicon carbide particulate composites have wide ranging applications in automobile, aerospace and military industries because of their attractive properties such as high strength-to weight ratio, high wear resistance, high temperature stability etc. From the machining point of view, these are one of the most difficult-to-machine materials, primarily due to the presence of SiC reinforcements causing an excessive wear of cutting tools during machining. On the other hand aluminium-graphite composites are widely used in tribological applications because of their excellent antifriction properties, wear resistance and antiseizure characteristics. Investigations have been carried out in this work to assess the machinability of aluminium matrix composites containing both SiC and graphite particulates as reinforcements. Turning experiments have been conducted on Aluminium-Graphite-Silicon Carbide hybrid composites using Carbide and PCD tool inserts to determine the flank wear. Experiments have been carried out based on Central Composite Design approach.

scholarly journals Effect of Microstructure of Fe-C-V Alloys on Selected Functional Properties

2014 ◽  
Vol 14 (3) ◽  
pp. 33-36 ◽  
Author(s):  
M. Kawalec ◽  
J. Kozana
Keyword(s):  
Wear Resistance ◽  
Cast Iron ◽  
Chemical Composition ◽  
White Cast Iron ◽  
High Wear Resistance ◽  
Cast Alloys ◽  
Vanadium Carbides ◽  
Good Workability ◽  
Conventional Machining ◽  
Very High

Abstract The cast alloys crystallizing in Fe-C-V system are classified as white cast iron, because all the carbon is bound in vanadium carbides. High vanadium cast iron has a very high abrasion resistance due to hard VC vanadium carbides. However, as opposed to ordinary white cast iron, this material can be treated using conventional machining tools. This article contains the results of the group of Fe-C-V alloys of various microstructure which are been tested metallographic, mechanical using an INSTRON machine and machinability with the method of drilling. The study shows that controlling the proper chemical composition can influence on the type and shape of the crystallized matrix and vanadium carbides. This makes it possible to obtain a high-vanadium cast iron with very high wear resistance while maintaining a good workability.

MOLITE 4

Alloy Digest ◽  
1985 ◽  
Vol 34 (9) ◽  
Keyword(s):  
Wear Resistance ◽  
High Speed ◽  
Thin Sheet ◽  
High Speed Steel ◽  
Heat Treating ◽  
Cold Extrusion ◽  
High Wear Resistance ◽  
Red Hardness ◽  
Twist Drills ◽  
Very High

Abstract MOLITE 4 is a high-carbon, high-vanadium, tungsten-molybdenum high-speed steel that approaches the ultimate in wear resistance for high-speed steels in this group. The advantages in using this steel comprise (1) Very high wear resistance, (2) High red hardness, (3) Good toughnes and (4) Moderate grindability. Among its many uses are punches and dies for blanking and forming thin sheet, milling cutters, twist drills, reamers, forming rolls, cold-extrusion punches and draw dies. This datasheet provides information on composition, physical properties, hardness, and elasticity. It also includes information on forming, heat treating, and machining. Filing Code: TS-447. Producer or source: Columbia Tool Steel Company.

TLP NINE

Alloy Digest ◽  
2001 ◽  
Vol 50 (4) ◽  
Keyword(s):  
Wear Resistance ◽  
High Temperature ◽  
Powder Metallurgy ◽  
Impact Toughness ◽  
Physical Properties ◽  
Heat Treating ◽  
High Impact ◽  
High Wear Resistance ◽  
Temperature Performance ◽  
Very High

Abstract Timken Latrobe Steel TLP Nine is made by powder metallurgy. It is an air-hardening tool steel with very high wear resistance and high impact toughness. This datasheet provides information on composition, physical properties, hardness, and elasticity. It also includes information on high temperature performance as well as heat treating and machining. Filing Code: TS-585. Producer or source: Timken Latrobe Steel.

AL TECH A-HT

Alloy Digest ◽  
1986 ◽  
Vol 35 (5) ◽  
Keyword(s):  
Heat Treatment ◽  
Fracture Toughness ◽  
Wear Resistance ◽  
Cold Work ◽  
Heat Treating ◽  
High Wear Resistance ◽  
Aisi Type ◽  
Low Distortion ◽  
Specialty Steel ◽  
Very High

Abstract AL TECH A-HT is a tool steel for difficult cold-work applications. It is somewhat similar to AISI Type A2 in alloy content but with increased wear resistance. Additions of titanium and tungsten produce hard, long-wearing carbides that help to decrease galling and metal pick-up. The main advantages of AL TECH A-HT are: (1) Very high wear resistance, (2) Good toughness, (3) Air hardening and (4) Low distortion in heat treatment. A-HT is used where better wear resistance is required than is attainable using AISI Type A2 or better toughness than AISI Type D2. This datasheet provides information on composition, physical properties, microstructure, hardness, elasticity, and compressive strength as well as fracture toughness. It also includes information on forming, heat treating, and machining. Filing Code: TS-457. Producer or source: AL Tech Specialty Steel Corporation.

Sign in / Sign up

Export Citation Format

Share Document