Effects of Floor Material, Surface Condition, and Foot Moving Speed on the Coefficient of Friction on the Floor

2013 ◽  
Vol 303-306 ◽  
pp. 2704-2707
Author(s):  
Kai Way Li ◽  
Chan Chi Lin
Keyword(s):  
Coefficient Of Friction ◽  
Surface Condition ◽  
Reaction Force ◽  
Force Platform ◽  
Material Surface ◽  
Sliding Speed ◽  
The Coefficient Of Friction ◽  
Male Subjects ◽  
Floor Material ◽  
Moving Speed

A laboratory study was conducted to measure the coefficient of friction between the foot and the floor under three surface and two foot sliding speed conditions. A force platform was adopted to measure the ground reaction force (GRF) of the foot on the floor. The coefficient of friction was calculated as the ratio of vertical and horizontal GRF. Five male subjects were recruited. They were requested to slide their right foot on the tested floor which was mounted on the force platform. The results indicated that floor material, surface condition, and foot sliding speed were all significant factor affecting the COF. Ceramic tile had lower COF under all surface and sliding speed conditions as compared to steel, wood, and vinyl tiles.

Friction and Wear of Unlubricated Steel Surfaces at Speeds up to 655 FT/S

1965 ◽  
Vol 180 (1) ◽  
pp. 531-548 ◽  
Author(s):  
S. W. E. Earles ◽  
M. J. Kadhim
Keyword(s):  
Oxide Layer ◽  
Coefficient Of Friction ◽  
Normal Load ◽  
Surface Condition ◽  
Relative Increase ◽  
Gradual Change ◽  
Sliding Speed ◽  
Specimen Diameter ◽  
Abrasive Surface ◽  
The Coefficient Of Friction

The friction force between 1/8, 3/32 and 1/16 in diameter, and the wear of 3/32 in diameter, specimens of En 1A steel sliding on a disc of S62 steel are measured at speeds between 93 and 655 ft/s, the normal load on the specimen varying between 0.2 and 4.5 lbf. The coefficient of friction is shown to be dependent on sliding speed, normal load and specimen diameter, and to be a function of N1/2 U, where N is the normal load and U is the sliding speed. It is suggested that the coefficient of friction is dependent on the specimen contact surface condition which is dependent on the specimen surface temperature. There is evidence to suggest a gradual change in the mechanism of sliding with increasing magnitude of N1/2 U from, (i) metallic abrasion and tearing of an oxide layer, (ii) to skidding on and shallow ploughing of an oxide layer, (iii) to gliding over and shearing of a soft surface layer. It appears that the coefficient of friction is independent of, whereas specimen wear is dependent on, the disc surface condition. At low loads the material transferred from the specimen tends to form a continuous oxide layer on the disc., while at high loads there is the formation and tearing of a thick oxide layer, presenting a more abrasive surface to the specimen with a relative increase in wear. Generally specimen wear per sliding distance increases with N and decreases with U.

Paper 16: Friction in Wet Clutches

1967 ◽  
Vol 182 (14) ◽  
pp. 132-138 ◽  
Author(s):  
E. M. Evans ◽  
J. Whittle
Keyword(s):  
Coefficient Of Friction ◽  
Power Transmission ◽  
Sliding Speed ◽  
Friction Materials ◽  
Friction Characteristics ◽  
Sliding Surfaces ◽  
Base Oils ◽  
Wet Friction ◽  
Friction Clutch ◽  
The Coefficient Of Friction

This paper is intended to demonstrate that designers of wet clutches for power transmission can obtain the optimum friction characteristics for specific applications by considering the interaction between friction materials and lubricants. A friction clutch plate rig is described and the friction results obtained are presented. It is shown that a wide variation of coefficients of friction and frictional characteristics in wet friction clutches can be obtained by changing the oils and friction materials. In particular the coefficient of friction is dependent upon (1) the oil, (2) the materials of the sliding surfaces, (3) sliding speed, and (4) temperature. It is also shown that the coefficient of friction is affected by ( a) refining treatment given to the oil, ( b) different base oils, and ( c) additives.

Measurement of Tribological Parameters

2014 ◽  
Vol 875-877 ◽  
pp. 496-499 ◽  
Author(s):  
Eva Labašová ◽  
Rastislav Ďuriš
Keyword(s):  
Coefficient Of Friction ◽  
Test Equipment ◽  
Tribological Characteristics ◽  
Sliding Speed ◽  
Sliding Joint ◽  
The Coefficient Of Friction ◽  
Run Up ◽  
Tribological Parameters

The contribution deals with measurement of the coefficient of friction in the sliding joint. Rotanional sliding pair, which was tested, is described in this paper. Their tribological characteristics were measured by test equipment Tribotestor`89. The value of the coefficient of friction for the bushings from brass, aluminium and polyamide for chosen load (the sliding speed, loading, duration) are analysed in the paper. The largest decrease in the size of the coefficient of friction was recorded for bushings from aluminium, its value have decreased by 87.5% during the run up. Decrease of the coefficient of friction was recorded about 82% for bushings from brass and about 72% for bushings from polyamide. Run up lasted 10 minutes in all tests.

Friction of a Rubber Wedge Sliding on Glass

1991 ◽  
Vol 64 (1) ◽  
pp. 108-117 ◽  
Author(s):  
C. W. Extrand ◽  
A. N. Gent ◽  
S. Y. Kaang
Keyword(s):  
Coefficient Of Friction ◽  
Applied Load ◽  
Unit Length ◽  
Sliding Speed ◽  
Normal Loading ◽  
Contact Width ◽  
Wide Range ◽  
The Coefficient Of Friction ◽  
Apparent Coefficient Of Friction ◽  
Pressure Independent

Abstract The contact width, and hence contact area, for an elastic wedge pressed against a rigid flat surface appears to be proportional to the applied load per unit length. For a particular rubber sample, the reciprocal of the constant of proportionality, i.e., the mean normal pressure, was 130 kPa, i.e., about 7% of the tensile modulus E of the material. It was also independent of sliding speed over the range examined. Thus, a sharp wedge gave a relatively high loading pressure, independent of the applied load. As a result, the coefficient of friction was also independent of applied load over a wide range. The coefficient of friction was measured for a wedge of an unfilled natural rubber vulcanizate over wide ranges of sliding speed (50 µm/s to 100 mm/s) and test temperature (3°C to 63°C). It was found to increase with sliding speed and decrease with temperature over these ranges. The results at different temperatures were superposable using the WLF rate-temperature equivalence to create a master curve of friction vs. reduced sliding speed, rising from a value of about 1.5 at high temperatures and low speeds to about 5 at low temperatures and high speeds. Chlorination of a thin surface region reduced the coefficient of friction and its dependence on speed and temperature. It then became similar to that typically found for thermoplastics, 0.4 to 0.7. The geometry of sliding a flexible strip against a rigid curved surface caused high values of the apparent coefficient of friction to be obtained at relatively small departures from normal loading. In an extreme case, frictional seizure was observed when a high-friction sample contacted the glass surface at an angle of about 15° to the direction of loading. The apparent coefficient of friction then became indefinitely large. This same phenomenon of abnormally large frictional effects would be expected to occur in the case of conventional windshield-wiper blades, sliding over curved glass windshields.

Influence of corrosion on prestress strands

1999 ◽  
Vol 26 (6) ◽  
pp. 782-788 ◽  
Author(s):  
SMR Lopes ◽  
L MLP Simões
Keyword(s):  
Mechanical Properties ◽  
Coefficient Of Friction ◽  
Prestressed Concrete ◽  
Surface Condition ◽  
Fatigue Properties ◽  
Structural Members ◽  
The Coefficient Of Friction ◽  
Bond Characteristics ◽  
Beams And Girders ◽  
Prestressed Beams

Corrosion on prestress strands affects their mechanical properties as well as the coefficient of friction in the surface strand/duct. In previous research on prestress beams, the authors have observed different coefficients of friction depending on the surface condition of the strands and wires used in investigation. Some of the strands used for the experiments were stored for some months in the laboratory and gained some rust on the surface. This was enough to influence the coefficient of friction in a noticeable manner. To study the influence of corrosion on the mechanical properties of prestress strands several samples were stored under different environmental conditions to produce various levels of corrosion. These samples were tested afterwards to determine the influence of corrosion on fatigue properties and the coefficient of friction. Apart from the coefficient of friction, light rust decreases none of the other studied mechanical properties of the strands and may even increase the bond characteristics. The presence of rust does not necessarily mean that the strands should be rejected. The work described in this paper was conducted to investigate the level of rust that could be considered acceptable and how corrosion influences some mechanical properties of prestressing strands.Key words: reinforced concrete, prestressed concrete, prestressed beams and girders, structural design, structural members, corrosion, fatigue, losses.

scholarly journals RESEARCH OF WORKING BENEFITS OF BEARINGS APPLICATION OF MATHEMATICAL METHOD

2021 ◽  
Vol 08 (04) ◽  
pp. 95-98
Author(s):  
Sevinc Abasova Sevinc Abasova
Keyword(s):  
Coefficient Of Friction ◽  
Thermoplastic Elastomer ◽  
Operating Parameters ◽  
Specific Load ◽  
Sliding Speed ◽  
Friction Units ◽  
Joint Influence ◽  
The Coefficient Of Friction ◽  
Heavy Loads ◽  
Main Operating

It is known that the service life of oilfield machines and mechanisms is to a certain extent determined by the operability of friction units, the operation of which, as a rule, occurs under severe conditions (heavy loads, abrasive aqueous medium, etc.). It is also known that the determining parameters in the units of machines and mechanisms (lubricated with water) with polymer elements are specific load, sliding speed and relative clearance. In the field, these factors affect the coefficient of friction together, therefore, the study of their influence [µ = f (p, ʋ, ψ)] on the coefficient of friction is possible only with the use of mathematical modeling. We have studied the nature of the joint influence of the main operating parameters on the performance of the ison thermoplastic elastomer plain bearings. Keywords: Operation, polymer elements, field conditions, bearings, sliding speed.

Paper 19: Unlubricated Sliding at High Speeds between Copper and Steel Surfaces

1966 ◽  
Vol 181 (15) ◽  
pp. 25-30 ◽  
Author(s):  
M. J. Kadhim ◽  
S. W. E. Earles
Keyword(s):  
Oxide Layer ◽  
Coefficient Of Friction ◽  
Normal Load ◽  
Sliding Speed ◽  
Wear Rates ◽  
High Speeds ◽  
Before And After ◽  
The Coefficient Of Friction ◽  
Steel Disc ◽  
Steel Surfaces

Experiments are described in which stationary copper specimens are rubbed in a normal atmosphere against a rotating S62 steel disc under normal loads up to 4·5 lbf. The coefficient of friction is measured at sliding speeds of 93, 220, 328, and 490 ft/s using ⅛-in diameter specimens. Except at the lowest speed a gradual buildup of a continuous copper oxide layer on the disc track is observed with increasing normal load together with a corresponding decrease in the coefficient of friction. Having established an oxide layer on the track the coefficient of friction observed is low for all normal loads. The coefficient of friction is shown to decrease with normal load N and sliding speed U, to be a function of N1/2 U, and to depend on the state of the disc surface. Wear of -in diameter specimens is measured by weighing before and after a test. The wear rate is shown to decrease with sliding speed and increase with load, and for speeds of 220 and 328 ft/s to be a function of N/U. The wear rates measured at 93 ft/s are the same function of N/U for low values of N/U.

The Effect of Controlled Frequency and Amplitude of Vibration on Friction

2009 ◽  
Vol 147-149 ◽  
pp. 380-386 ◽  
Author(s):  
Jamil Abdo ◽  
Amer Al-Yhmadi
Keyword(s):  
Surface Roughness ◽  
Coefficient Of Friction ◽  
Nonlinear Function ◽  
Polynomial Equation ◽  
304 Stainless Steel ◽  
Sliding Speed ◽  
Pin On Disc ◽  
The Coefficient Of Friction ◽  
Friction Function ◽  
Alloy 6061

An in-house pin-on-disc apparatus is designed and constructed to perform the tests and the design of experiments technique is utilized to determine the effect of vibration, amplitude of vibration, surface roughness, and sliding speed and their cross influence on coefficient of friction for 304 stainless steel and Alloy 6061 Aluminum. The design is performed using response surface method (RSM). The coefficient of friction (CoF) is analyzed as a nonlinear function of the factors and predicted by a second-order polynomial equation. Results suggested that the presence of vibration affect the friction function CoF considerably for both metals. The friction function linearly decreases with the increases of vibration and amplitude of vibration, non-linearly decreases with the increases of sliding speed and linearly increases with the increases of the surface roughness until the middle range is reached and then there is non-linearly decrease thereafter. Similar trends of friction functions are observed for Alloy 6061 Aluminum with a reduction of almost 15% except for the case with amplitude of vibration where the variation showed more significant affect on the friction function when Alloy 6061 Aluminum disk is used.

Investigation of Vibration Induced by Sliding Down an Ice Plane

2019 ◽  
Vol 800 ◽  
pp. 298-302
Author(s):  
Mārtiņš Irbe ◽  
Marina Cerpinska ◽  
Karlis Agris Gross
Keyword(s):  
Coefficient Of Friction ◽  
High Sensitivity ◽  
Processing Conditions ◽  
Sliding Speed ◽  
Ice Surface ◽  
The Coefficient Of Friction

Many studies use an inclined ice plane to determine the effect of different materials and processing conditions on sliding over an ice surface. Experiments measure the sliding time at different stages on the track to determine the sliding speed and the coefficient-of-friction. Here, the sliding body vibrations and, the oscillations in axial directions are addressed. This paper analyzes the sample’s acceleration by attaching a portable High Sensitivity 1.25g USB Accelerometer and compares the data with 3D CAM modeling results to identify the causes for interrupted sliding.

Sign in / Sign up

Export Citation Format

Share Document