Development of a method and an apparatus for tribotechnical tests of materials under loose abrasive friction

Abstract Friction is usually discussed in terms of contributions from two processes: deformation and adhesion. This terminology has been retained in discussions of lubricated friction of rubber although there is not apparent any clear mechanism by which adhesion might occur. Our study of wet friction leads us to suggest that the components making up frictional resistance to sliding might more appropriately be referred to as deformation and abrasive components. On this basis, there is an obvious mechanism for both processes, and some of the disagreements about interpretation of certain experimental results may be resolved. The basis for our interpretation is implicit in the literature but was originally expressed somewhat tentatively and has not been restated in recent discussions. Greenwood and Tabor pointed out that hysteretic losses make an important contribution to friction of rubber sliding on a lubricated surface and that this contribution is independent of asperity size or distribution so long as only the asperities support the load and the radius of curvature at the asperity tip is above a critical limit which is remarkably low. Further, the experiments of Sabey showed that it was difficult to obtain coefficients higher than 0.4 with spherical sliders. Mean average local pressures high enough to give high friction coefficients could be obtained only with sharp asperities. In the laboratory experiment these were cones. Greenwood and Tabor found that with these damage to the rubber becomes visible at just the semiangle at which the coefficient began to rise abruptly (Figure 1). It is entirely reasonable to call the process causing this damage abrasive friction.

Download Full-text

Design of experiments analysis of abrasive friction behavior of Al-TiB2 composites

Materials Today Proceedings ◽

10.1016/j.matpr.2019.06.705 ◽

2019 ◽

Vol 19 ◽

pp. 218-222 ◽

Cited By ~ 1

Author(s):

Avinash Gavel ◽

Suswagata Poria ◽

Prasanta Sahoo

Keyword(s):

Design Of Experiments ◽

Friction Behavior ◽

Abrasive Friction

Download Full-text

Mechanical properties of single-quasicrystalline AlCuCoSi

Journal of Materials Research ◽

10.1557/jmr.1991.1165 ◽

1991 ◽

Vol 6 (6) ◽

pp. 1165-1168 ◽

Cited By ~ 55

Author(s):

R. Wittmann ◽

K. Urban ◽

M. Schandl ◽

E. Hornbogen

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Friction Coefficient ◽

Modulus Of Elasticity ◽

Vickers Indentation ◽

Indentation Method ◽

Abrasive Friction ◽

Highly Strained ◽

First Time

The mechanical properties of single-quasicrystals of decagonal AlCoCuSi have been studied for the first time by applying the Vickers indentation method. The hardness has been determined as H ≃ 9.6 MPa. Estimates for the modulus of elasticity and the fracture toughness are given. The quasicrystals are highly strained internally. Scratching experiments show slight anisotropies in the abrasive friction coefficient. The dominant abrasive mechanism is microplowing.

Download Full-text

Electrochemical behavior of the materials of pharmaceutical equipment under the conditions of abrasive friction

Materials Science ◽

10.1007/s11003-006-0033-5 ◽

2005 ◽

Vol 41 (5) ◽

pp. 693-697

Author(s):

O. K. Sevidova ◽

I. D. Roi ◽

I. I. Stepanova

Keyword(s):

Electrochemical Behavior ◽

Abrasive Friction

Download Full-text

Correlation between Cutting Forces and Tool Wear in High Speed Milling of Graphite

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.69-70.403 ◽

2009 ◽

Vol 69-70 ◽

pp. 403-407 ◽

Cited By ~ 1

Author(s):

Li Zhou ◽

Cheng Yong Wang ◽

Xiao Jun Wang ◽

Zhe Qin

Keyword(s):

Tool Wear ◽

Cutting Force ◽

Cutting Forces ◽

High Speed ◽

Cutting Tools ◽

Dynamic Force ◽

High Speed Milling ◽

Time Frequency ◽

Abrasive Friction ◽

Force Components

Cutting tools suffer severe abrasive friction and wear in high speed milling of graphite. Cutting forces were measured and analyzed using time-frequency analysis method to reveal the correlation between cutting force variations and tool wear evolution. The static and dynamic force components increased prominently with tool wear. The cutting force Fy was found the most sensitive to the tool wear evolution. The waveform of cutting force became periodic and irregular with the increase of tool wear. Good correlation was found between the first force harmonic and tool wear.

Download Full-text

FROM ACTIVE SHARE TO CUTTING APPARATUS

Vestnik of Kazan state agrarin university ◽

10.12737/article_59ad08548e9049.06731194 ◽

2017 ◽

Vol 12 (2) ◽

pp. 88-92

Author(s):

Александр Мудров ◽

Aleksandr Mudrov

Keyword(s):

Service Life ◽

Energy Costs ◽

Agricultural Machinery ◽

Abrasive Medium ◽

Roller Bearings ◽

Abrasive Friction ◽

The Subject ◽

Special Arrangement

The subject of the article relates to agricultural machinery, namely, to the working units of root harvesting machines and to cutting device of harvesting machines. In both the first and second designs, work is performed in an abrasive medium, which reduces their service life and increases energy costs. The devices are proposed, in which the work is carried out in the absence of abrasive friction in the working parts. The novelty of devices is marked by patents for invention. The effect is achieved by the special arrangement of the geometric axes of the joints of the links, which are designed on needle roller bearings, by the simplicity of structures, by reduction of energy costs for the drive of the working units, by reliability and durability.

Download Full-text

Laser-Spark Modification of the Surfaces of Structural Materials by the Example of St3

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.284.1268 ◽

2018 ◽

Vol 284 ◽

pp. 1268-1272

Author(s):

S.G. Kuptsov ◽

V.V. Shimov ◽

R.S. Magomedova

Keyword(s):

Wear Resistance ◽

Construction Materials ◽

Chemical Properties ◽

Fold Increase ◽

Hard Alloys ◽

Laser Surface Modification ◽

Abrasive Friction ◽

Laser Spark ◽

Physical And Chemical

The paper considers a technology for hardening construction materials using the hybrid (laser-spark) method by the example of steel St3 using hard alloys (VK8, stellite PR-V3K). A significant (several-fold) increase in the wear resistance of the coatings obtained is shown at resistance to abrasive friction due to the good quality of the coating layer and its microhardness (up to 60 GPa). Optimum modes for electrical spark and laser surface modification are proposed. Some physical and chemical properties of the coatings obtained (thickness, roughness, wear resistance, microhardness), as well as their dependence on the hybrid machining modes, are studied. The prospectivity of applying the hybrid (laser-spark) method for hardening of machine parts in order to increase their resistance to abrasive wear during friction is justified.

Download Full-text