System Dependence of Running-In Attractor Derived From Lubricated Sliding Contact of Steel Alloys 52100 and 1045

2018 ◽  
Vol 140 (5) ◽  
Author(s):  
Yuankai Zhou ◽  
Xue Zuo ◽  
Hua Zhu ◽  
Yujie Fan
Keyword(s):  
Correlation Dimension ◽  
Sliding Contact ◽  
Range Analysis ◽  
Steel Alloys ◽  
Nonlinear Parameters ◽  
System Parameters ◽  
Standard Block ◽  
Disk Friction ◽  
Pin On Disk ◽  
Variation Tendency

The steady-state described by running-in attractor in the perspective of nonlinearity, is closely dependent on the running-in parameters. To study the dependence of running-in attractor on system parameters, pin-on-disk friction tests were performed. A suitable contact between pin and disk was ensured by a self-adaptive pin holder, standard block, and self-adapting amendment with sandpaper. Range analysis of correlation dimension, predictability, and entropy shows that running-in attractor is system dependent, which is manifested by the dependence of nonlinear parameters of the attractor on the running-in parameters. Further results indicate that the correlation dimension and entropy increase with load and velocity, but decrease along with initial roughness of a harder counterface, and predictability shows an inverse variation tendency with correlation dimension and entropy.

Structural and Tribological Properties of TiC/C/Ag Coatings in Vacuum and Ambient Environments

2001 ◽  
Vol 697 ◽  
Author(s):  
Jose L. Endrino ◽  
Jose J. Nainaparampil ◽  
James E. Krzanowski
Keyword(s):  
Carbon Content ◽  
Laser Energy ◽  
High Vacuum ◽  
Ambient Conditions ◽  
Friction Behavior ◽  
Cross Sectional ◽  
Reduced Modulus ◽  
Custom Made ◽  
Disk Friction ◽  
Pin On Disk

AbstractTiC/C/Ag coatings were deposited by magnetron sputtering pulsed laser deposition (MSPLD) combining sputtering from a custom made Ti-Ag (60:40) target with the ablation of carbon. Energy disperse spectroscopy (EDS) was used to determine the elemental composition, and x-ray diffraction (XRD) and cross-sectional scanning electron microscopy (XSEM) to examine the structure of the films. Hardness and reduced modulus measurements were acquired using a nanoindentation technique. The pin-on-disk friction test was used to study the friction behavior of the deposited samples in high vacuum and ambient conditions. Variations in the laser energy and the power of the sputtering gun yielded a set of samples with carbon content that ranged from 15.0 to 95.6 percent. The hardest samples with the highest reduced modulus were those with a moderate carbon content and that were shown to form a titanium carbide phase. Tribological results indicated that there is an optimum composition of a TiC/C/Ag coating (~25 at.% carbon) for which it can be reversible and provide lubrication in both ambient and vacuum.

Comparison in Tribological Properties of YBa2Cu3OX/Ag and Bi2Sr2CaCu2OX/Ag Self-Lubricating Composites

2011 ◽  
Vol 291-294 ◽  
pp. 34-40
Author(s):  
Hua Tang ◽  
Wen Jing Li ◽  
Chang Sheng Li
Keyword(s):  
Friction Coefficient ◽  
Tribological Properties ◽  
Room Temperature ◽  
Superconducting Transition ◽  
Friction Test ◽  
Average Value ◽  
Structure And Morphology ◽  
Disk Friction ◽  
Pin On Disk ◽  
Self Lubricating Composites

The YBa2Cu3Ox/Ag and Bi2Sr2CaCu2Ox/Ag self-lubricating composites were prepared using powder metallurgic method. The crystal structure and morphology of the as-synthesized samples were characterized by XRD and SEM. The YBa2Cu3Ox/Ag and Bi2Sr2CaCu2Ox/Ag self-lubricating composites were found to compose of superconductor phase and Ag phase. The tribological properties from ultra-low temperature to room temperature of the composites were studied by pin-on-disk friction test. It was found that the friction coefficients of pure YBa2Cu3Ox(YBCO) and Bi2Sr2CaCu2Ox(BSCCO) were both dropped abruptly when the temperature cooled below the superconducting transition temperature. At room temperature, the friction coefficient of pure YBa2Cu3Oxis 0.68~0.95, when mixing 15wt% Ag, the friction coefficient of the sample decreased to the lowest value 0.11. The friction coefficient of pure Bi2Sr2CaCu2Ox is 0.15~0.17, When Ag content reach 10wt%, the coefficient was lowest (average value is 0.13). The addition of appropriate amount of Ag obviously improve the tribological property of YBCO, while only slightly meliorate that of BSCO. On the other hand, the YBCO/Ag composites exhibit better tribological properties than BSCCO/Ag composites at higher load under the same experimental condition.

Detecting Chaotic Behavior in Agricultural Exchange-traded Funds

2018 ◽  
Vol 3 (1) ◽  
Author(s):  
Jo-Hui Chen ◽  
Batsukh Tushigmaa ◽  
Yu-Fang Huang
Keyword(s):  
Correlation Dimension ◽  
Chaotic Behavior ◽  
Conditional Heteroskedasticity ◽  
Exchange Traded Funds ◽  
Range Analysis ◽  
Random Data ◽  
Standardized Residuals ◽  
Dimension Analysis ◽  
Rescaled Range ◽  
Rescaled Range Analysis

<p>This study investigates the chaos effect of agricultural exchange-traded funds (ETFs) using Brock, Dechert, and Scheinkman test, rescaled range analysis, and correlation dimension analysis. The standardized residuals from generalized autoregressive conditional heteroskedasticity models are fitted into eight ETFs and examined in each case for evidence of chaotic behavior. This study also examines whether or not the ETFs are consistent with the chaos effect based on the underlying random data with trend-reinforcing series. Research results outline the financial insights for the agricultural ETF field of investment forecasting to eliminate trading emotions, while pursuing considerable profitable experience for investors.</p>

A Technique for Estimating Linear Parameters Using Nonlinear Restoring Force Extraction in the Absence of an Input Measurement

2005 ◽  
Vol 127 (5) ◽  
pp. 483-492 ◽  
Author(s):  
Muhammad Haroon ◽  
Douglas E. Adams ◽  
Yiu Wah Luk
Keyword(s):  
System Identification ◽  
Nonlinear System ◽  
Nonlinear System Identification ◽  
Restoring Force ◽  
Nonlinear Parameters ◽  
System Parameters ◽  
System Data ◽  
Vehicle Suspension System ◽  
Two Stages ◽  
Parameter Estimation Techniques

Conventional nonlinear system identification procedures estimate the system parameters in two stages. First, the nominally linear system parameters are estimated by exciting the system at an amplitude (usually low) where the behavior is nominally linear. Second, the nominally linear parameters are used to estimate the nonlinear parameters of the system at other arbitrary amplitudes. This approach is not suitable for many mechanical systems, which are not nominally linear over a broad frequency range for any operating amplitude. A method for nonlinear system identification, in the absence of an input measurement, is presented that uses information about the nonlinear elements of the system to estimate the underlying linear parameters. Restoring force, boundary perturbation, and direct parameter estimation techniques are combined to develop this approach. The approach is applied to experimental tire-vehicle suspension system data.

Novel Composite Coatings With 3D Coating Architectures for Tribological Applications Fabricated Using Semiconductor Patterning Processes

2002 ◽  
Vol 750 ◽  
Author(s):  
James E. Krzanowski ◽  
Jose L. Endrino ◽  
Karl Hirschman
Keyword(s):  
Composite Coatings ◽  
Substrate Surface ◽  
Three Dimensional ◽  
Wear Test ◽  
Dimensional Structure ◽  
Structural Modifications ◽  
Wear Protection ◽  
Carbide Coatings ◽  
Disk Friction ◽  
Pin On Disk

ABSTRACTComposite coatings consisting of hard compounds and soft solid lubricant phases have been actively investigated as tribological coatings for reducing friction while improving wear resistance. In most cases structural modifications in these coatings have been achieved by either natural phase separation or sequential layer deposition. In this study, we explore the concept of creating a three-dimensional structure in a tribological composite coating by using well-established semiconductor patterning methods. Using photolithography, we have patterned the substrate surface with a regular array of micron-size islands. The substrate was then coated with various metal and carbide coatings, including Cr and TiC, using sputter deposition. The substrates were sonicated in a solvent to remove the photoresist islands leaving an array of holes. MoS2 was then deposited onto the substrates. A pin-on-disk friction and wear test was conducted on a TiC/MoS2 sample to examine the effects of these islands on wear morphology. The results showed that the MoS2-filled holes can act as lubricant reservoirs, and the areas of the sample coated with TiC/MoS2 provided better wear protection than areas coated with only MoS2.

scholarly journals PEMANFAATAN SERAT PELEPAH KELAPA SAWIT SEBAGAI BAHAN PEMBUATAN KAMPAS REM SEPEDA MOTOR

2021 ◽  
Vol 10 (2) ◽  
pp. 155
Author(s):  
Guntoro Guntoro ◽  
Ingrid Ovie Yosephine ◽  
Simon Simanjuntak
Keyword(s):  
Friction Coefficient ◽  
Alumina Powder ◽  
Rockwell Hardness ◽  
Brake Pads ◽  
Hardness Level ◽  
Powder Composition ◽  
A Value ◽  
Disk Friction ◽  
Pin On Disk ◽  
Palm Frond

Brake pads are generally made of asbestos, which is less environmentally friendly and widely available in nature, therefore motorcycle brake pads are made that utilize palm frond fibers filled with alumina powder and bonded to a polyurethane matrix. This research was conducted at the Laboratory of Material Testing of Industrial Chemical Technology Polytechnic (PTKI) Medan. Research was carried out from February-July 2020, using two test, namely the Rockwell Hardness level test and the Pin On Disk Friction Coefficient test. The result showed that oil palm frond fibers can be made into motorcycle brake pads with the addition of alumina powder according to the predetermined composition. After going through the test, the Rockwell hardness level was obtained in A2 treatment (6% Alumina) with the highest and best hardness level, namely 52.75 Kg. And after testing the friction coefficient of the Pin On Disk type, brake pads from palm frounds with the addition of alumina powder composition which have the lowest coefficient value of the best are obtained in treatment A2 (6% Alumina) with a value of 0.000765 N/mm2. Keywords : biocomposite, brake shoes, palm fround fibers, alumina powder

Detecting Chaotic Behavior in Agricultural Exchange-traded Funds

2018 ◽  
Vol 3 (1) ◽  
Author(s):  
Jo-Hui Chen ◽  
Batsukh Tushigmaa ◽  
Yu-Fang Huang
Keyword(s):  
Correlation Dimension ◽  
Chaotic Behavior ◽  
Conditional Heteroskedasticity ◽  
Exchange Traded Funds ◽  
Range Analysis ◽  
Random Data ◽  
Standardized Residuals ◽  
Dimension Analysis ◽  
Rescaled Range ◽  
Rescaled Range Analysis

<p>This study investigates the chaos effect of agricultural exchange-traded funds (ETFs) using Brock, Dechert, and Scheinkman test, rescaled range analysis, and correlation dimension analysis. The standardized residuals from generalized autoregressive conditional heteroskedasticity models are fitted into eight ETFs and examined in each case for evidence of chaotic behavior. This study also examines whether or not the ETFs are consistent with the chaos effect based on the underlying random data with trend-reinforcing series. Research results outline the financial insights for the agricultural ETF field of investment forecasting to eliminate trading emotions, while pursuing considerable profitable experience for investors.</p>

Preparation and Tribological Performance of Silica/Ethylene-Octene Copolymer Nanocomposites

2014 ◽  
Vol 606 ◽  
pp. 41-46
Author(s):  
Ke Sheng Cao ◽  
Song Tian Li ◽  
Yong Hua Cheng ◽  
Xiao Liang Guo
Keyword(s):  
Laser Scanning ◽  
Friction And Wear ◽  
Silica Particles ◽  
Polymer Materials ◽  
Matrix Composites ◽  
Nano Silica ◽  
Mechanical And Tribological Properties ◽  
Disk Friction ◽  
Ethylene Octene Copolymer ◽  
Pin On Disk

The maleic anhydride-grafted ethylene-octene copolymer (POE-g-MAH) and 2, 3-epoxy propoxy propyltrimethoxysilicane (KH-560) modified nano-silica particles/ POE nanocomposites were fabricated by solution coprecipitation. Tribological behaviors of these nanocomposites were investigated using a pin-on-disk friction and wear tester under dry friction condition, and worn surfaces were studied by scan electron microscope (SEM) and color 3D laser scanning microscope, respectively. The results indicated that the addition of the low inclusion (more than 10 wt%) of nano-silica particles could improve the reducing-friction and anti-wear abilities of the POE matrix composites, and modified nano-silica as the filler are superior to nano-silica in terms of the ability of decreasing friction coefficient and wear rate of the POE polymer materials. In both cases, appropriate treatments could effectively improve the mechanical and tribological properties of the POE matrix composites due to the enhanced nanosilicas-matrix interfacial bonding.

scholarly journals Tribological changes of tooth enamel-mullite/3Y-TZP couple in artificial saliva

2020 ◽  
Author(s):  
Yanqi Huang ◽  
Zhuan Li ◽  
Peng-fei Liu ◽  
Yan-meng Cheng ◽  
Wen-jie Li ◽  
...  
Keyword(s):  
Tooth Enamel ◽  
Artificial Saliva ◽  
Composite Ceramic ◽  
Fatigue Wear ◽  
Gel Casting ◽  
Potential Applications ◽  
Acute Cytotoxicity ◽  
Disk Friction ◽  
Friction Method ◽  
Pin On Disk

Abstract In-situ mullite toughened 3Y-TZP composite ceramic (mullite/3Y-TZP) with excellent mechanical properties was fabricated by gel-casting. The cytotoxicity of mullite/3Y-TZP was determined by both extract and direct contact methods, and the results indicated that mullite/3Y-TZP had no acute cytotoxicity. Furthermore, the tribological properties of the tooth enamel sliding against mullite/3Y-TZP in artificial saliva were investigated by using the pin-on-disk friction method. The friction coefficient (µ) between the two friction samples was about 0.464 with a stable friction process, and both of them showed slight wear. Analysis of the wear surface and debris demonstrated that the tooth enamel mainly suffered from fatigue wear accompanied by mild adhesive wear, while mullite/3Y-TZP showed slight abrasive wear. This result indicated that mullite/3Y-TZP had good wear resistance and showed potential applications in dental material.

Sign in / Sign up

Export Citation Format

Share Document