Microstructure Evolution Induced by Sliding-Based Surface Thermomechanical Treatments - Application to Pure Copper

2016 ◽  
Vol 879 ◽  
pp. 915-920 ◽  
Author(s):  
G. Kermouche ◽  
G. Jacquet ◽  
C. Courbon ◽  
J. Rech ◽  
Y.Y. Zhang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Wear Resistance ◽  
Microstructural Evolution ◽  
Sliding Friction ◽  
Pure Copper ◽  
Cutting Speed ◽  
Friction Contact ◽  
Paper Surface ◽  
Set Up ◽  
Contact Pressures

In this paper, surface microstructural evolution induced by processes based on repeated sliding (friction) contact such as burnishing or machining is investigated. A set-up designed for simulating contact pressures and cutting speed occurring during machining is used to create a gradient of nanomicro-structure. It is composed of a top surface recrystallized layer and a sub-surface made of ultrafine grains over a depth larger than 100 μm. Induced-mechanical properties as well as resulting wear resistance are discussed. A conclusion is brought on the benefits of this new kind of sliding-based surface mechanical treatments (SMT).

STUDY OF WEAR RESISTANCE OF REINFORCED POLYAMIDE COMPOSITES FOR METAL-POLYMER GEAR DRIVES

Tribologia ◽  
2018 ◽  
Vol 279 (3) ◽  
pp. 19-23
Author(s):  
Myron CHERNETS ◽  
Serge SHIL'KO ◽  
Mikhail PASHECHKO
Keyword(s):  
Wear Resistance ◽  
Sliding Friction ◽  
Gear Wheel ◽  
Gear Ratio ◽  
Carbon Fibres ◽  
Gear Drive ◽  
Glass Fibres ◽  
Gear Drives ◽  
Contact Pressures ◽  
Metal Polymer

An experimental study of the wear resistance of two dispersion-filled composite materials based on polyamide used in metal-polymer gear drives with a 30% volume content of short glass or carbon fibres was performed according to the technique proposed by the authors. As a result of tribotests in the “pin-disk” scheme, the mass wear of these composites was determined under dry friction conditions for steel 45 at room temperature in the range of contact pressures of 10–40 MPa, as well as the kinetics of the coefficient of sliding friction and the contact temperature of the tribosystem elements. It was established that polyamide strengthened by carbon fibres has almost four times higher wear resistance in comparison with a polyamide filled with glass fibres. The wear resistance characteristics that are the basic parameters of the tribokinetic wear model are calculated, using the durability of the straight spur metal-polymer gear drive on the basis of the original calculation method. It was established that gear drive durability with a pinion or a wheel reinforced with carbon fibres is more than eight times the durability of gear drive with gear wheels from polyamide filled with glass fibres. The gear drive durability with the steel pinion and the composite gear wheel increases in proportion to the gear ratio as compared to the gear drive with the composite pinion and the steel wheel. The change in the maximum contact pressures in the mesh interval was calculated.

Friction and Wear Behavior of Nano-Al2O3 Particles Reinforced Copper Matrix Composites

2014 ◽  
Vol 137 (1) ◽  
Author(s):  
Guobin Li ◽  
Ningning Peng ◽  
Di Sun ◽  
Shude Sun
Keyword(s):  
Wear Resistance ◽  
Friction And Wear ◽  
Sliding Friction ◽  
Wear Behavior ◽  
Pure Copper ◽  
Copper Matrix ◽  
Powder Metallurgy Method ◽  
Matrix Composites ◽  
Al2o3 Composite ◽  
Average Size

A series of copper–Al2O3 composite materials (CACMs) with 0, 2, 4, and 6 wt.% of Al2O3 (average size about 80 nm) was fabricated by powder metallurgy method. The tribological behavior of CACMs was investigated by a ring-on-block sliding friction test. The results show that the hardness and the wear resistance of CACMs are improved by the addition of Al2O3. The CACMs with 0% Al2O3 (pure copper) shows the mechanism of adhesive wear and have very poor wear resistance. By comparing with the pure copper, the wear resistance of the CACMs with 2% and 6% Al2O3 is improved. When the proportion of Al2O3 is 4%, slightly abrasive wear occurs at the interface between two sliding surfaces, and the CACMs achieve higher wear resistance in comparison to that with 2% and 6% Al2O3.

Mechanical Behavior of Quasicrystals

MRS Bulletin ◽  
1997 ◽  
Vol 22 (11) ◽  
pp. 65-68 ◽  
Author(s):  
Knut Urban ◽  
Michael Feuerbacher ◽  
Markus Wollgarten
Keyword(s):  
Mechanical Properties ◽  
Wear Resistance ◽  
High Temperature ◽  
Low Temperature ◽  
Mechanical Behavior ◽  
Melting Temperature ◽  
Sliding Friction ◽  
Great Promise ◽  
Brittle To Ductile Transition ◽  
Physical Reasons

Scientists have studied the mechanical properties of quasicrystalline materials for quite some time. However the difficulty in obtaining material of reasonable quality hampered systematic investigations. The progress in materials preparation in recent years has triggered new activity in this field. Furthermore the new ternary and multicomponent alloys have demonstrated great promise for use as coatings with good wear resistance and low coefficients of sliding friction. However the physical reasons for these properties and their correlation with the particular structure of quasicrystals are still not understood. As in conventional alloys, experiments under well-defined conditions are required that can serve as a basis for understanding the intrinsic mechanical properties of quasicrystals. Such studies are now increasingly possible after the development of techniques to grow larger single quasicrystals up to a few centimeters in size directly from the melt.Since the mechanical behavior of quasicrystalline alloys is to a great extent determined by a brittle-to-ductile transition at about 70% of the absolute melting temperature, it is useful to discuss the mechanical properties with reference to appropriately defined low-temperature and high-temperature regions.

scholarly journals Effects of Cr and Zr Addition on Microstructures, Compressive Properties, and Abrasive Wear Behaviors of In Situ TiB2/Cu Cermets

Materials ◽  
2018 ◽  
Vol 11 (8) ◽  
pp. 1464 ◽  
Author(s):  
Feng Qiu ◽  
Xiangzheng Duan ◽  
Baixin Dong ◽  
Hongyu Yang ◽  
Jianbang Lu ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Wear Resistance ◽  
Compressive Strength ◽  
Yield Strength ◽  
Abrasive Wear ◽  
Pure Copper ◽  
Abrasive Particle ◽  
Wear Volume ◽  
Wear Properties

: In situ micro-TiB2/Cu cermets with a different TiB2 content (40, 50, and 60 vol %) were successfully fabricated by combustion synthesis (CS) and hot press consolidation in Cu-Ti-B systems. In addition, different contents of Cr and Zr were added to the Cu-Ti-B systems. The microstructure, mechanical properties, and abrasive wear properties of the TiB2/Cu cermets were investigated. As the ceramic content increased, the yield strength and compressive strength of the cermets were found to increase, while the strain decreased. An increase in load and abrasive particle size caused the wear volume loss of the TiB2/Cu cermets to increase. When the ceramic content was 60 vol %, the wear resistance of the TiB2/Cu cermets was 3.3 times higher than that of pure copper. The addition of the alloying elements Zr and Cr had a significant effect on the mechanical properties of the cermets. When the Cr content was 5 wt %, the yield strength, ultimate compressive strength, and microhardness of the cermets reached a maximum of 997 MPa, 1183 MPa, and 491 Hv, respectively. Correspondingly, when the Zr content was 5 wt %, those three values reached 1764 MPa, 1967 MPa, and 655 Hv, respectively, which are 871 MPa, 919 MPa, and 223 Hv higher than those of the unalloyed cermets. The wear mechanism of the in-situ TiB2/Cu cermets, and the mechanisms by which the strength and wear resistance were enhanced by the addition of Zr, were preliminarily revealed.

Influence of SiO2 Micro- Particles on Microstructure, Mechanical Properties and Wear Resistance of UHMWPE Based Composite under Dry Sliding Friction

2018 ◽  
Vol 769 ◽  
pp. 152-157 ◽  
Author(s):  
Noppanuch Puangmalee ◽  
Narongrit Sonjaitham ◽  
Setthawit Saengthip ◽  
Noppanan Mungnuae ◽  
Surachade Solklin ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Wear Resistance ◽  
Sliding Friction ◽  
Polymeric Composite ◽  
Weight Fraction ◽  
Dry Sliding ◽  
Compression Process ◽  
Micro Particles ◽  
The Matrix ◽  
Dry Sliding Friction

This research investigated the influence of silicon dioxide (SiO2) with particle size of 5 micron on microstructure, mechanical properties and wear resistance of UHMWPE polymeric composite materials under dry sliding friction that was tested by Block–on–ring technique according to ASTM G77. Bulk UHMWPE composite specimen was reinforced with SiO2 particles by weight fraction of 0.1, 0.2, 0.3, 0.4, 0.5, 1, 2, 3, 4 and 5 wt.%. Specimen was performed by hot compression process with the compression forming conditions at the temperature of 202°C, pressure of 9.7 MPa and exposure time of 77 minutes. It was found that, SiO2 particle fraction in the range of not exceed than 0.5 wt.% did not affect to change microstructure of the specimen, which its microstructure did not significantly different from the initial UHMWPE specimen due to SiO2 particles were dispersed uniformly in the UHMWPE matrix. Its microstructure appeared in a spherulitic structure pattern. However, the increasing of SiO2 more than 0.5 wt.% affect to changed microstructure due to the SiO2 particles separated from the matrix and accumulated on the UHMWPE matrix. For the case of mechanical and wear resistance properties, the increasing of SiO2 particle of 0.5-1 wt.% affect to increased various mechanical properties to have a highest value and lowest wear rate as compared with initial UHMWPE up to 1.7 times. After that, the increasing of SiO2 particle affect to mechanical properties and wear resistance were decreased, except for the hardness that continuously increased according to the increasing of SiO2.

MODELING OF THE GRINDING PROCESS BY MICRO-CUTTING SINGLE ABRASIVE GRAINS. PART 2. WEAR ASSESSMENT OF ABRASIVE GRAINS

2021 ◽  
pp. 10-16
Author(s):  
Yu. M. Zubarev ◽  
A. V. Priemyshev
Keyword(s):  
Mechanical Properties ◽  
Wear Resistance ◽  
Performance Indicators ◽  
Cutting Speed ◽  
Physical And Mechanical Properties ◽  
Grinding Process ◽  
Grinding Wheels ◽  
Micro Cutting ◽  
Technological Factors ◽  
Abrasive Grains

One of the main performance indicators of grinding wheels is their wear resistance, which is largely determined by the wear resistance of abrasive grains. Data on the influence of physical and mechanical properties of the material of blanks and the material of abrasive grains, together with technological factors, on the micro-cutting process are presented. The influence of the cutting speed on the intensity and character of wear of abrasive grains is shown.

Characterization of Cu-Al2O3 and Ni-Al2O3 Nanocomposites Electrodeposited on Copper Substrate

2016 ◽  
Vol 846 ◽  
pp. 471-478 ◽  
Author(s):  
Eydar Tey ◽  
Mansor Hashim ◽  
Ismayadi Ismail
Keyword(s):  
Mechanical Properties ◽  
Wear Resistance ◽  
Metal Matrix ◽  
Low Cost ◽  
Pure Copper ◽  
Average Particle Size ◽  
Composite Films ◽  
Copper Substrate ◽  
Copper Plate ◽  
Average Particle

In the present work, it was attempted to electrodeposit Cu-Al2O3 and Ni-Al2O3 metal matrix composite (MMC) coatings onto a copper substrate using a modified Watts bath containing dispersed nanosized Al2O3 with an average particle size of 50 nm. The prepared nanocomposite coatings were subjected to different tests to characterize their surface morphology, crystalline structure and mechanical properties. The microstructure and composition of the composite films were studied with Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD) techniques. The use of nanoparticles could change the microstructure and morphology of the electrodeposits, depending on the metal matrix composites. The hardness and wear resistance tests were carried out on nanocomposite coating samples to investigate the mechanical properties. The co-deposited Al2O3 nanoparticles in the deposit increased the hardness and wear resistance, which were closely related with Al2O3 content in the nanocomposites. The hardness of the Ni-Al2O3 coating increased by about 26.3 % compared to pure copper plate due to the dispersion hardening effect. The hardness of the Cu-Al2O3 coating decreased by about 25.2 % as compared to pure copper plate due to the minimization of surface energy and the surface porosity of the coating. The wear resistance of the Ni-Al2O3 coating on the copper substrate was higher than that of Cu-Al2O3 as deduced from the lower mass loss of the former. The novelty of this project is the creation of very hard coating using a relatively low cost method.

Wear Resistance of Hypereutectoid Steel Alloyed with Copper and Aluminum

2015 ◽  
Vol 788 ◽  
pp. 274-280
Author(s):  
Natalia Stepanova ◽  
Elena Lozhkina ◽  
Alexey Razumakov ◽  
Anna Losinskaya
Keyword(s):  
Mechanical Properties ◽  
Wear Resistance ◽  
Cast Iron ◽  
Sliding Friction ◽  
Hypereutectoid Steel ◽  
Abrasive Particles ◽  
Relative Wear ◽  
Relative Wear Resistance ◽  
Fixed Abrasive ◽  
Lamellar Pearlite

The structure, mechanical properties and wear resistance of hypereutectoid steel containing 0.09-8.97 wt. %copper were studied. It is found that an increase in copper increases lamellar pearlite microhardness. Triboengineering testings under conditions of sliding friction show that wear resistance of hypereutectoid steel alloyed with 8.97 wt. % copper is ~3.5 times higher than the wear resistance of bronze and by ~23 % higher than the wear resistance of bearing cast iron. Under conditions of friction on fixed abrasive particles a relative wear resistance of the hypereutectoid steel alloyed with copper is ~3 times higher than a relative wear resistance of bronze.

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