Experimental Characterization of Sliding Friction: Crossing From Deformation to Plowing Contact

2000 ◽  
Vol 122 (4) ◽  
pp. 856-863 ◽  
Author(s):  
M. R. Lovell ◽  
Zhi Deng ◽  
M. M. Khonsari
Keyword(s):  
Friction Coefficient ◽  
Sliding Friction ◽  
Normal Load ◽  
Operating Conditions ◽  
Experimental Characterization ◽  
Lubricant Oil ◽  
Ball Diameter ◽  
Sliding Friction Coefficient ◽  
Pin On Disk

A pin-on-disk tribometer was used to investigate the influence of several parameters on the sliding friction coefficient between hard and deformable surfaces. Pin (1045 tool steel) and disk (aluminum 1100) were utilized to simulate the interaction of a harder tool sliding relative to a softer deformable workpiece. Friction coefficient results were obtained at 561 distinct operating conditions by varying the ball diameter (3.18, 6.35, and 12.70 mm), lubricant (oil B, oil A, and grease), sliding speed (0.1∼0.8 m/s) and normal load (50∼1200 g). Several relationships which characterize the behavior of the friction coefficient as a function of the shear factor, τk, are established. the importance of these relationships, as related to stamping and forming processes, is discussed. [S0742-4787(00)01703-3]

Wear Characterization of Aluminum Lubricated with Palm Olein at Different Normal Load

2014 ◽  
Vol 554 ◽  
pp. 401-405 ◽  
Author(s):  
Samion Syahrullail ◽  
Ahmad Mohd Azmi ◽  
Norzahir Sapawe ◽  
Amir Khalid
Keyword(s):  
Friction Coefficient ◽  
Palm Olein ◽  
Normal Load ◽  
Pure Aluminum ◽  
Experimental Conditions ◽  
Sliding Mechanism ◽  
Different Types ◽  
Pin On Disk ◽  
Wear Characterization

The pin-on-disk tester is a method used for investigating wear. The sliding mechanism between the pin and the disc experimentally creates wear. In this paper, the wear characteristics of an aluminium pin sliding on an SKD11 disc lubricated with double fraction palm olein were investigated. The pin was made from pure aluminum A1100. The results were compared with those of tests in which the disc was lubricated with commercial hydraulic oil. In both sets of experimental conditions, the normal load varied from 4 to 10 kg. Rotational speed was set to 1200 rpm. From this study, it was found that different types of lubricant affect the wear progression and friction coefficient during a sliding movement. The wear progression and friction coefficient depend also on the load applied, surface roughness, pressure applied and contact surface area.

Numerical investigation of sliding friction behaviour and mechanism of engineering surfaces

2019 ◽  
Vol 71 (2) ◽  
pp. 205-211 ◽  
Author(s):  
Xiaogang Zhang ◽  
Yali Zhang
Keyword(s):  
Surface Roughness ◽  
Friction Coefficient ◽  
Sliding Friction ◽  
Normal Load ◽  
Numerical Results ◽  
Operating Conditions ◽  
Friction Mechanism ◽  
Content Type ◽  
Optimal Surface ◽  
Friction Behaviour

Purpose This study aims to investigate the sliding friction behaviour and mechanism of engineering surfaces. Design/methodology/approach A new numerical approach is proposed. This approach derives the macroscale friction coefficient from microscale asperity interactions. By applying this approach, the sliding friction behaviour under different operating conditions were investigated in terms of molecular and mechanical components. Findings Numerical results demonstrate an independent relationship between normal load and friction coefficient, which is governed by the saturated plastic ratio. Numerical results also demonstrate that under very small load, an increase in load increases the friction coefficient. In addition, numerical results confirm the existence of optimal surface roughness where the friction coefficient is the lowest. For the surface profiles used in the current calculation, an optimal surface roughness value is obtained as Rq = 0.125 μm. Originality/value This new approach characterizes the deterministic relationship between macroscale friction coefficient and microscale asperity molecular/mechanical interactions. Numerical results facilitate the understanding of sliding friction mechanism.

Sliding Behavior of Alumina/Nickel and Alumina/Nickel Aluminide Couples at Room and Elevated Temperature

1988 ◽  
Vol 110 (4) ◽  
pp. 646-652 ◽  
Author(s):  
Peter J. Blau ◽  
Charles E. DeVore
Keyword(s):  
Elevated Temperature ◽  
Friction Coefficient ◽  
Nickel Aluminide ◽  
Room Temperature ◽  
Elevated Temperatures ◽  
Sliding Friction ◽  
Surface Damage ◽  
Polycrystalline Alumina ◽  
Ordered Intermetallic ◽  
Pin On Disk

Nickel aluminide alloys are ordered intermetallic compounds which show promise for elevated temperature applications, some of which involve sliding contact. The present investigation was conducted to develop an initial understanding of the unlubricated sliding behavior of a nickel aluminide alloy at room and elevated temperatures. In particular, the variations in the friction coefficient and the wear track morphology during the break-in stage and subsequent transitions were studied. Pin-on-disk experiments were conducted at room temperature and at 650° C (923° K) in air using fixed 9.5 mm diameter polycrystalline alumina balls as the pin material. To provide a comparison in behavior, nickel (Ni-200) disks were tested under the same conditions. The sliding friction coefficient of alumina on nickel aluminide was considerably higher than that for alumina on nickel at room temperature, but it was only slightly higher at 650° C. The wear was similar for both materials at room temperature, but the nickel aluminide exhibited relatively mild wear at 650° C, displaying less severe surface damage than the nickel. Work on identifying key friction and wear mechanisms and on evaluating the temperature limitations for future applications will continue.

scholarly journals Friction Resistance of Refined, Bleached and Deodorized (RBD) Palm Olein Using Modified Pin-on-disk Tribotester

2013 ◽  
Vol 60 (1) ◽  
Author(s):  
M. I. Izhan ◽  
A. K. Mohammed Rafiq ◽  
S. Syahrullail
Keyword(s):  
Friction Coefficient ◽  
Wear Rate ◽  
Palm Olein ◽  
Normal Load ◽  
Mineral Oil ◽  
Friction Resistance ◽  
Rbd Palm Olein ◽  
Large Production ◽  
Wear Friction ◽  
Pin On Disk

Daya geseran untuk minyak sawit olein yang ditapis, diluntur dan dinyahbau (RBD olein) telah dinilai dengan menggunakan alat tribotester pin-atas-cakera. RBD olein telah dipilih kerana sifat-sifat unggul tribologi dan pengeluarannya yang besar di Malaysia. Dalam kajian ini, 5ml minyak RBD olein telah digunakan pada cakera beralur. Pin yang mempunyai hujung rata telah digunakan sebagai bahan ujikaji. Cakera dan pin diperbuat daripada titanium alloy. Beban normal yang dikenakan pada pin ialah 4.96N dan 19.68N. Ujikaji telah dijalankan selama satu jam. Kadar haus pin dan pekali geseran telah dikira. Ujikaji yang sama telah dijalankan dengan menggunakan minyak hidraulik komersial dan minyak mineral jenis parafinik yang tidak mengandungi bahan tambah. Pekali geseran yang dihasilkan oleh pelinciran minyak sawit RBD olein adalah terendah berbanding minyak mineral parafinik pada kedua-dua jenis beban(4.96N dan 19.68N). Bagaimanapun, minyak sawit RBD olein menunjukkan kadar haus yang tinggi berbanding minyak mineral parafinik pada beban normal 19.68N. Kata kunci: Pin-atas-cakera; minyak sawit; palm olein; haus; pekali geseran A friction resistance of refined, bleached and deodorized (RBD) palm olein was evaluated using a modified pin-on-disk tribotester. RBD palm olein was selected due to its superior tribological properties and large production in Malaysia. In this research, 5ml of RBD palm olein was applied on the rotating grooved-disk. The flat-ended pin was used as a specimen. The material was titanium for both pin and disk. The normal loads applied are 4.96N and 19.68N. The experiments were run for one hour. The wear rate of the pin and friction coefficient was calculated. Same experiments were conducted using commercial hydraulic oil and additive-free paraffinic mineral oil. The results were compared with RBD palm olein. The friction coefficient with the lubrication of RBD palm olein was the lowest for 4.96N and 19.68N under normal load conditions. Wear rate obtained by RBD palm olein at normal load 4.96N was the lowest; however, RBD palm olein showed a high wear rate when high normal load (19.68N) was applied. Keywords: Pin-on-disk; palm oil; palm olein; wear; friction coefficient

scholarly journals DESCRIPTIVE MODEL OF SLIDING FRICTION PROCESSES

2015 ◽  
Vol 2 ◽  
pp. 227
Author(s):  
Andris Martinovs ◽  
Vladimir Gonca
Keyword(s):  
Friction Coefficient ◽  
Surface Area ◽  
Contact Surface ◽  
Sliding Friction ◽  
Friction Model ◽  
Friction Process ◽  
Contact Surface Area ◽  
Optimal Surface ◽  
Sliding Friction Coefficient ◽  
The Mathematical Model

Paper analyses the sliding friction coefficient of rubber on concrete, timber and ceramic tile surfaces depending on the weight of the sliding object and contact surface area. It has been established that increase in the weight of the object makes sliding friction coefficient to grow. In the case of increase in size of contact area, sliding friction coefficient between rubber and concrete also increases, but it decreases between rubber- timber and rubber- tile. The mathematical model for description of sliding friction process has been developed which can be used to determine optimal surface area and a pattern as well as optimal weight of the sliding object in order to provide sufficient sliding friction. Model has five independent constants. It includes the contact surface area, the weight and the velocity of the sliding object, sliding friction coefficient, temperature and time.

scholarly journals EXPERIMENTAL STUDY OF THE INFLUENCE OF RUBBER PROPERTIES ON SLIDING FRICTION IN DRY CONTACT

2017 ◽  
Author(s):  
A. V. Morozov
Keyword(s):  
Friction Coefficient ◽  
Viscoelastic Properties ◽  
Sliding Friction ◽  
Normal Load ◽  
Bulk Temperature ◽  
Master Curves ◽  
Rubber Compounds ◽  
Different Temperatures ◽  
Dry Conditions ◽  
Friction Measurements

This study is devoted to experimental research of rubber friction in sliding contact with rough surface. Influence of pressure, bulk temperature and sliding velocity on friction coefficient in dry conditions is analysed for two rubber compounds with different viscoelastic properties. Grosch method of master curves construction is used for analysing of friction measurements. Such analysis is performed for different temperatures and velocities at constant normal load. The obtained friction master curves are combined into a single friction map. The friction maps demonstrate the influence of viscoelastic properties of rubber on friction coefficient in dry rough contact. Also friction maps show the influence of adhesion and hysteresis contributions into friction coefficient for different rubber compounds.

scholarly journals Experimental Characterization and Evaluation of the Vibroacoustic Field of Hydraulic Pumps: The Case of an External Gear Pump

Energies ◽  
2020 ◽  
Vol 13 (24) ◽  
pp. 6639
Author(s):  
Sangbeom Woo ◽  
Andrea Vacca
Keyword(s):  
Operating Conditions ◽  
Plate Motion ◽  
Sound Power ◽  
Gear Pump ◽  
Experimental Characterization ◽  
Noise Performance ◽  
Noise Sources ◽  
Iso Standards ◽  
Minimum Number

This paper presents the experimental characterization of the vibroacoustic fields and the evaluation of noise performances of hydraulic pumps. Research on hydraulic pump noise has traditionally focused on the fluid-borne noise sources, and very often the analyses of vibration and noise have been performed focusing on a few local points. This trend results in the lack of investigation on the overall behaviors of vibroacoustic fields of hydraulic pumps, and it has been one of the obstacles to understand the complete mechanisms of noise generation. Moreover, despite the existence of the ISO standards for the determination of noise levels, diverse metrics have been used for the evaluation of noise performances of the pumps, but the adequacy of these metrics has not been carefully examined. In this respect, this paper aims at introducing a way to characterize and interpret the measured vibroacoustic field and providing proper methods which are also capable of applying the ISO standards for the fair assessment of pump noise performances. For the characterization of the vibroacoustic field, operational deflection shapes (ODS) and corresponding radiated sound fields are visualized at harmonics of the pumping frequency by using a spectral analysis. Observations are made regarding the motions of the pump and its mounting plate and the resultant radiated noise, depending on the frequency, as well as their correlation. A numerical analysis using the Rayleigh integral equation is also performed to further investigate the contribution of the mounting plate motion on the noise radiation. For the evaluation of noise performance, two different units are tested at multiple operating conditions, and comparisons are made based on their measured sound power levels (SWLs) and sound pressure levels (SPLs). The results emphasize the importance of SWL measurement for the fair noise performance evaluation, and the two methods are proposed as practices to determine the minimum number of measurement points for practicability and to have reliable sound power determination for hydraulic pumps.

Sign in / Sign up

Export Citation Format

Share Document