scholarly journals Effect of the electromagnetic compound field on the grain growth and wear resistance of a Cu-Pb monotectic alloy

2020 ◽  
Vol 54 (2) ◽  
pp. 243-249
Author(s):  
Z. Li ◽  
T. Yu ◽  
D. Wang ◽  
G. Geng
Keyword(s):  
Wear Resistance ◽  
Grain Growth ◽  
Monotectic Alloy

scholarly journals Effect of High Density Electric Current Pulse on Solidification of Cu-37.4 wt.%Pb Monotectic Alloy Melt

2019 ◽  
Vol 26 (1) ◽  
pp. 34-40
Author(s):  
Teng MA ◽  
Guihong GENG ◽  
Xiaosi SUN ◽  
Xi HAO ◽  
Weixin HAO
Keyword(s):  
Wear Resistance ◽  
Electric Current ◽  
Current Pulse ◽  
Metal Cluster ◽  
High Density ◽  
Formation Mechanisms ◽  
Electric Current Pulse ◽  
Monotectic Alloy ◽  
Scanning Calorimetry ◽  
Cluster Theory

The effect of high-density electric current pulse (ECP) on the solidification of Cu-37.4 wt.%Pb monotectic alloy melt was investigated. The microstructure formation mechanisms of ECP were clarified according to liquid metal cluster theory. The results demonstrated that with ECP treatment, the microstructure of Cu-Pb monotectic alloy became finer, the distribution of Pb phase in the matrix was more even and the solute trapping was significantly apparent. Based on the metal liquid cluster theory under ECP, the solid solubility increase result might be due to the salvation clusters increase under the action of pulse current, leading to the binding force increase among solute atoms and solvent atoms. Simultaneously, the aforementioned results were verified through the Differential Scanning Calorimetry (DSC) curve analysis. The results of hardness test, anti-friction test and wear- resistance test show that the ECP can enhance the hardness, improve the properties of anti-friction and wear-resistance of the alloy.

Synthesis of WC-10wt.%Co Nanocrystalline Powders with Grain Growth Inhibitor by MTP

2007 ◽  
Vol 534-536 ◽  
pp. 1237-1240 ◽  
Author(s):  
Dong Kyu Park ◽  
Kwang Chul Jung ◽  
Jin Chun Kim ◽  
Sung Yeal Bae ◽  
In Sup Ahn
Keyword(s):  
Grain Size ◽  
Wear Resistance ◽  
Liquid Phase ◽  
Grain Growth ◽  
Growth Inhibitor ◽  
Liquid Phase Sintering ◽  
Nanocrystalline Powders ◽  
Grain Growth Inhibitor ◽  
Nano Crystalline ◽  
Carburizing Process

To improve the fracture strength and wear resistance of WC-Co cemented carbide, various technologies have been developed related producing the nano crystalline. There have been extensive studied conducted to retard grain growth during liquid phase sintering. However, when this inhibitor is added by simple mixing, a micro-pores forms during sintering In this study, WC-Co nanocrystalline powders with grain growth inhibitor in the site were prepared by MTP (Mechano-Thermic carburizing Process) to minimize this formation of micro pores and to retard grain growth effectively during sintering. In addition, then the phase and grain size of WC-Co nanocrystalline powders were evaluated according to the condition of MTP.

Mechanism Research of Pr6O11 Addition on Wear Resistance of Alumina Ceramics

2015 ◽  
Vol 1104 ◽  
pp. 27-30
Author(s):  
Yang Wu ◽  
Bo Lin Wu ◽  
Si Long Bi
Keyword(s):  
Wear Resistance ◽  
Rare Earth ◽  
Grain Boundaries ◽  
Grain Growth ◽  
Interface Reaction ◽  
Rare Earth Ions ◽  
Alumina Ceramics ◽  
Composite Oxide ◽  
Influence Mechanism ◽  
Mechanism Research

Many literatures reported rare earth ions would segregate at grain boundaries toinhibit grain growth and improve the ceramic performance. However, the mutualinfluence between segregation and alumina grains was rarely seen in thereports. In this article, interface reaction between single crystal alumina (inorder to eliminate the influence of grain boundaries) and praseodymium oxidewas designed to further understand the influence mechanism. The resultssuggested that a composite oxide was formed at the junctions. Besides, largestresses produced between the composite oxide and alumina because of the thermalexpansion coefficient difference. This stresses would weaken grain boundariesbonding strength and reduce wear resistance.

scholarly journals Wear Resistance Mechanism of Alumina Ceramics Containing Gd2O3

Materials ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 2054 ◽  
Author(s):  
Tingting Wu ◽  
Jianxiu Su ◽  
Yongfeng Li ◽  
Hongyuan Zhao ◽  
Yaqi Zhang ◽  
...  
Keyword(s):  
Grain Size ◽  
Wear Resistance ◽  
Wear Rate ◽  
Grain Boundary ◽  
Grain Growth ◽  
Water Environment ◽  
Resistance Mechanism ◽  
Alumina Ceramics ◽  
Industry Standard ◽  
Chinese Industry

Excellent wear resistance of alumina ceramics is a desirable quality for many products. The purpose of this work was to improve the wear resistance of 99% alumina ceramics in an Al2O3–Gd2O3–SiO2–CaO–MgO (AGSCM) system. The content of Gd2O3 varied from 0.01% to 1%. A test of wear rate was performed in a ball milling apparatus in a water environment according to the Chinese industry standard. The compositions and microstructure of this material, as well as the effect of bulk density on wear rate, were studied. The effect of Gd2O3 on phases, grain growth mode, and grain boundary cohesion was investigated. It was found that Gd2O3 could refine grain size, form compressive stress of the grain boundary, and promote the crystallization of CaAl12O19. The wear rate of this material was as low as 0.00052‰ (the Chinese industry standard wear rate is ≤0.15‰). The mechanisms for wear resistance of AGSCM ceramics were also determined.

Silicon nitride nanoceramics densified by dynamic grain sliding

2010 ◽  
Vol 25 (12) ◽  
pp. 2354-2361 ◽  
Author(s):  
Mathias Herrmann ◽  
Zhijian Shen ◽  
Ingrid Schulz ◽  
Jianfeng Hu ◽  
Bostjan Jancar
Keyword(s):  
Wear Resistance ◽  
Phase Transformation ◽  
Silicon Nitride ◽  
Grain Growth ◽  
Major Phase ◽  
Phase Constituent ◽  
Plasma Sintering ◽  
Spark Plasma ◽  
Sintering Conditions ◽  
Full Densification

The densification behaviors of two silicon nitride nanopowder mixtures based respectively on α-Si3N4 and β-Si3N4 as the major phase constituent were studied by spark plasma sintering. Sintering conditions were established where a low viscous liquid not in equilibrium with the main crystalline constituent(s) stimulated the grain sliding yet did not activate the reprecipitation mechanism that unavoidably yields grain growth. By this way of dynamic grain sliding full densification of silicon nitride nanoceramics was achieved with no noticeable involvement of α- to β-Si3N4 phase transformation and grain growth. This processing principle opens the way toward flexible and precise tailoring of the microstructures and properties of Si3N4 ceramics. The obtained silicon nitride nanoceramics showed improved wear resistance, particularly under higher Hertzian stresses.

Application of TEM to Deformation, Wear, and Fracture of Ceramics

1974 ◽  
Vol 32 ◽  
pp. 472-473
Author(s):  
B. J. Hockey
Keyword(s):  
Wear Resistance ◽  
High Temperature ◽  
Mechanical Behavior ◽  
Brittle Materials ◽  
High Temperature Strength ◽  
Wide Range ◽  
Corrosive Environments ◽  
Further Development

Ceramics, such as Al2O3 and SiC have numerous current and potential uses in applications where high temperature strength, hardness, and wear resistance are required often in corrosive environments. These materials are, however, highly anisotropic and brittle, so that their mechanical behavior is often unpredictable. The further development of these materials will require a better understanding of the basic mechanisms controlling deformation, wear, and fracture.The purpose of this talk is to describe applications of TEM to the study of the deformation, wear, and fracture of Al2O3. Similar studies are currently being conducted on SiC and the techniques involved should be applicable to a wide range of hard, brittle materials.

Grain Refinement in Titanium-Erbium Alloys

1974 ◽  
Vol 32 ◽  
pp. 522-523
Author(s):  
B. B. Rath ◽  
J. E. O'Neal ◽  
R. J. Lederich
Keyword(s):  
Electron Microscopy ◽  
Size Distribution ◽  
Grain Refinement ◽  
Grain Growth ◽  
Volume Fraction ◽  
Pure Titanium ◽  
Systematic Investigation ◽  
Second Phase ◽  
Titanium Matrix ◽  
Average Size

Addition of small amounts of erbium has a profound effect on recrystallization and grain growth in titanium. Erbium, because of its negligible solubility in titanium, precipitates in the titanium matrix as a finely dispersed second phase. The presence of this phase, depending on its average size, distribution, and volume fraction in titanium, strongly inhibits the migration of grain boundaries during recrystallization and grain growth, and thus produces ultimate grains of sub-micrometer dimensions. A systematic investigation has been conducted to study the isothermal grain growth in electrolytically pure titanium and titanium-erbium alloys (Er concentration ranging from 0-0.3 at.%) over the temperature range of 450 to 850°C by electron microscopy.

Microstructural characterization of a rapidly solidified Al-Fe-V-Si alloy for elevated temperature applications

1988 ◽  
Vol 46 ◽  
pp. 550-551
Author(s):  
R. E. Franck ◽  
J. A. Hawk ◽  
G. J. Shiflet
Keyword(s):  
High Temperature ◽  
Elevated Temperature ◽  
Grain Growth ◽  
Volume Fraction ◽  
Microstructural Characterization ◽  
Second Phase ◽  
Microstructural Stability ◽  
Elevated Temperature Strength ◽  
Temperature Applications

Rapid solidification processing (RSP) is one method of producing high strength aluminum alloys for elevated temperature applications. Allied-Signal, Inc. has produced an Al-12.4 Fe-1.2 V-2.3 Si (composition in wt pct) alloy which possesses good microstructural stability up to 425°C. This alloy contains a high volume fraction (37 v/o) of fine nearly spherical, α-Al12(Fe, V)3Si dispersoids. The improved elevated temperature strength and stability of this alloy is due to the slower dispersoid coarsening rate of the silicide particles. Additionally, the high v/o of second phase particles should inhibit recrystallization and grain growth, and thus reduce any loss in strength due to long term, high temperature annealing.The focus of this research is to investigate microstructural changes induced by long term, high temperature static annealing heat-treatments. Annealing treatments for up to 1000 hours were carried out on this alloy at 500°C, 550°C and 600°C. Particle coarsening and/or recrystallization and grain growth would be accelerated in these temperature regimes.

Abrasive wear of polymer/steel gear drives

2008 ◽  
Vol 4 (1) ◽  
pp. 1-26
Author(s):  
Gábor Kalácska
Keyword(s):  
Wear Resistance ◽  
Abrasive Wear ◽  
Material Selection ◽  
Solid Particles ◽  
Soil Types ◽  
General View ◽  
Modern Engineering ◽  
Clean Environment ◽  
Engineering Polymers ◽  
Plastic Gears

Research was performed on the friction, wear and efficiency of plastic gears made of modern engineering polymers and their composites both in a clean environment (adhesive sliding surfaces) and in an environment contaminated with solid particles and dust (abrasive), with no lubrication at all. The purpose is to give a general view about the results of abrasive wear tests including seven soil types as abrasive media. At the first stage of the research silicious sand was applied between the meshing gears and the wear of plastic and steel gears was evaluated and analyzed from the point of different material properties (elongation at break, hardness, yield stress, modulus of elasticity) and its combinations. The different correlations between the experienced wear and material features are also introduced. At the second stage of the project the abrasive sand was replaced with different physical soil types. The abrasive wear of gears is plotted in the function of soil types. The results highlight on the considerable role of physical soil types on abrasive wear resistance and the conclusions contain the detailed wear resistance. The results offer a new tribology database for the operation and maintenance of agricultural machines with the opportunity of a better material selection according to the dominant soil type. This can finally result longer lifetime and higher reliability of wearing plastic/steel parts.

Comparative high-temperature wear resistance of CHS88U-VI alloy and H30N50YU5T2 satellite

2014 ◽  
Vol 0 (4) ◽  
Author(s):  
Oleksandr M. Kostin ◽  
Anastasiia Yu. Butenko ◽  
Volodymyr O. Martynenko
Keyword(s):  
Wear Resistance ◽  
High Temperature ◽  
High Temperature Wear
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