Design of Experiment Analysis of Plain ZDDP Oil in the Presence of FeF3 Using Two Different Rotational Speeds and Extreme Contact Load

2011 ◽  
Author(s):  
Gabi Nehme
Keyword(s):  
Surface Temperature ◽  
Boundary Lubrication ◽  
Contact Surface ◽  
Design Of Experiment ◽  
Contact Temperature ◽  
Hertzian Contact ◽  
Contact Load ◽  
Lower Stage ◽  
Lower Load ◽  
The One

The purpose of this study was to investigate the effect of cooling contact surface temperature of the test cylinder when a rise in contact temperature over 100 degree C occurs during boundary lubrication tribological testing. The Hertzian contact pressure in a ball on cylinder tests will be optimized with respect to the contact temperature using Design of Experiment (DOE) software. Several boundary lubrication tests were conducted to study the behavior of 0.1 P% (phosphorus percentage) plain ZDDP oil in the presence of 0.4% FeF3 under two different rotational speeds (lower stage of 100 rpm for the first 5000 revolutions and higher stage of 700 rpm until failure or 100000 revolutions whichever comes first). The one rotational speed of 700 rpm until failure will be compared to the two speed stages under a contact cooling surface temperature and different contact loads (2.77GPa–3.8Gpa Hertzian contact pressures). The two different speed stages indicate better performance under an extreme contact load and a lower contact surface temperature; whereas higher contact surface temperature and lower load are needed for the one speed stage of 700 rpm cycle.

Analysis of 100 and 700 rpm Cycles in Boundary Lubrication Using Fluorinated Mix Interactions Under Extreme Boundary Lubrication

2010 ◽  
Author(s):  
Gabi Nehme
Keyword(s):  
Boundary Lubrication ◽  
Design Of Experiment ◽  
Friction And Wear ◽  
Solid Mechanics ◽  
Hertzian Contact ◽  
Engine Oil ◽  
Factors Affecting ◽  
Oil Formulation ◽  
The One ◽  
Significant Factors

Tribology and solid mechanics are essential when studying engine lubrications. Very reproducible boundary lubrication tests were conducted as part of Design of Experiment software (DOE) to study the behavior of fluorinated mix in developing environmentally friendly (reduced P and S) anti-wear additives for future engine oil formulations using ball on cylinder testing protocol. In this study fully formulated oil and ZDDP plain oils were tested under the protocol of two cycles. A 100 rpm cycle was used for the first 5000 revolutions and a 700 rpm cycle was used until failure or 100000 revolutions whichever comes first. All tests were generated under extreme boundary lubrication (Hertzian contact pressure of 2.72 GPa). Design of Experiment (DOE) with 2 level factorial was used to investigate the failure and wear responses with respect to fluorinated mix interactions in plain and fully formulated oils. The two cycle’s tests indicate better performance than the one cycle test. Findings indicate that the most significant factors, affecting friction and wear are fluorinated mix concentrations together with oil formulation.

Observation of Fatigue Fracture on PEEK Shaft against Alumina Bearing’s Ball under One-Point Rolling Contact

2016 ◽  
Vol 878 ◽  
pp. 137-141 ◽  
Author(s):  
Hitonobu Koike ◽  
Genya Yamaguchi ◽  
Koshiro Mizobe ◽  
Yuji Kashima ◽  
Katsuyuki Kida
Keyword(s):  
Fatigue Fracture ◽  
Rolling Contact Fatigue ◽  
Rolling Direction ◽  
Contact Fatigue ◽  
Rolling Contact ◽  
Hertzian Contact ◽  
Subsurface Crack ◽  
Mechanical Elements ◽  
The One ◽  
Alumina Ball

Tribological fatigue failure of the machined PEEK shaft was investigated through the one-point type rolling contact fatigue test between a PEEK shaft and an alumina ball, in order to explore fatigue fracture mechanism of frictional parts working at high frequency in various mechanical elements. Due to Hertzian contact of cyclic compressive stress, the subsurface crack occurred within approximately 300 μm depth from thesurface and propagated along the rolling direction. After that, the subsurface crack propagation direction changed toward the surface. The flaking occurred on the raceway of the PEEK shaft when the subsurface crack reached to the PEEK shaft surface.

The Effect of Trialkyl Phosphites and Other Oil Additives on the Boundary Lubrication of Ceramics: Friction of Silicon-Based Ceramics

1992 ◽  
Vol 114 (4) ◽  
pp. 653-658 ◽  
Author(s):  
Kei Demizu ◽  
Hiroyuki Ishigaki ◽  
Hideo Kakutani ◽  
Fukuzo Kobayashi
Keyword(s):  
Silicon Nitride ◽  
Boundary Lubrication ◽  
Carbon Chain ◽  
Hertzian Contact ◽  
Carbon Chain Length ◽  
Friction Coefficients ◽  
Oil Additives ◽  
Carbon Chains ◽  
Trialkyl Phosphites ◽  
Silicon Based

In order to examine the fundamental boundary lubrication properties of ceramics, reciprocating friction experiments of silicon based ceramics such as silicon carbide and silicon nitride were conducted with trialkyl phosphites and other oil additives. When ceramics were slid against ceramics, trialkyl phosphites with long carbon chains reduced the friction of silicon nitride markedly; the friction coefficients decreased with an increase in the carbon chain length. Other oil additives, however, did not greatly affect the friction. When ceramics were slid against metals, additives containing chlorine or sulfur increased friction of certain sliding couples. On the other hand, a trialkyl phosphite reduced friction and the friction coefficients increased with an increase in the maximum Hertzian contact pressure.

Temperature Distributions in Microscale Fractal-Like Branching Channel Networks

2003 ◽  
Author(s):  
Ali Y. Alharbi ◽  
Deborah V. Pence ◽  
Rebecca N. Cullion
Keyword(s):  
Surface Temperature ◽  
Boundary Layers ◽  
Heat Sinks ◽  
Dimensional Model ◽  
One Dimensional ◽  
Temperature Distributions ◽  
Fluid Properties ◽  
Minor Losses ◽  
Branching Flow ◽  
The One

Heat transfer to liquid flow through fractal-like branching flow networks is investigated using a three-dimensional computational fluid dynamics approach. Results are used to assess the validity of, and provide insight for improving, assumptions imposed in a previously developed one-dimensional model to predict wall temperature distributions along a fractal-like flow network. Assumptions in the one-dimensional model include (1) reinitiating thermal and hydrodynamic boundary layers following each bifurcation, (2) negligible minor losses at the bifurcations, and (3) constant thermo-physical fluid properties. It is concluded that temperature varying fluid properties and minor losses should be incorporated in the one-dimensional model to improve its predictive capabilities. No changes to the redevelopment of the boundary layers at each wall following a bifurcation are recommended. Surface temperature distributions along heat sinks with parallel and fractal-like branching flow networks are also investigated and compared. For the same observed maximum surface temperature between the two heat sinks, considerably lower temperature variations and pressure drops, greater than 50 percent, are noted for the fractal-like heat sink.

Tack of Pressure-Sensitive Tape

1957 ◽  
Vol 30 (3) ◽  
pp. 847-853 ◽  
Author(s):  
Franklin S. C. Chang
Keyword(s):  
Adhesion Strength ◽  
Contact Surface ◽  
Point Of View ◽  
New Method ◽  
Depression Effect ◽  
Paper Surface ◽  
Pressure Sensitive ◽  
The One ◽  
Limiting Value

Abstract A new method has been found, as a result of this investigation, for measuring the tack of pressure-sensitive tape, which is simple and precise enough for practical purposes. By using this method, tack testing yields reproducible quantitative records in lieu of the ambiguous descriptive results from the empirical finger test. In light of the fact that, of the tapes made with the same adhesive, the one with crepe paper gave lower tack than the one made of flat paper, surface of contact must be one of the factors determining tack. Any pressure applied on the tape after the tape is put on the testing panel would, to a certain extent, increase the contact surface, hence, the force required to peel the tape from the panel. The stiffness of paper, through the depression effect, would have the same effect on the peeling force, in this case, the adhesion strength. Since tack is defined to be free of added pressure and depression effect, this explains the independence of tack and dependence of adhesion strength on stiffness of paper. Fom this point of view, one may consider tack as the limiting value of adhesion strength.

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