width="189" height="75"
motorsports.sponsoredproperties.com > Blog > 2018 > May > 23

Day: May 23, 2018

Effect of Sintering Temperature on Friction Performance of Cu-based Nanometer Composites Reinforced by Nano SiO2 Particles

by

Abstract.

The Cu-based nanometer composites reinforced by 1.0 wt% nano-SiO2 particles (Cu/n-SiO2) were prepared by powder metallurgy at different sintering temperature. The friction performance of the composites were studied by ball-disk friction tester. The results indicate the dynamice friction coefficient and wear rate of the composites gradually increase with the sintering temperature increasing (between 800 and 950 ) ℃ .

Intorduction

The nano SiO2 particles are amorphous inorganic non-metallic materials, which have excellent properties such as wear resistance and corrosion resistance because of its small size effect, surface and interface effect and so on. The nano SiO2 are widely used in high polymer, ceramics, coatings and biomedical fields [1-2]. In recent years, nano-SiO2 particles are gradually used in Cu-based composites. Besides keeping copper’s original excellent conductivity, thermal conductivity and elastic-plastic properties, nano-SiO2 can enhance the strength a

Read More...

Sintering Applications

by

Preface

Materials science and engineering depends on three classes of materials namely metals, ceramics and polymers. The aim of this book is to help the graduate and doctoral students in materials science and related disciplines on the sintering of several materials. During the sintering process, changes occur in the microstructure because of decomposition or phase transformations. Three major changes commonly ocur during sintering. The grain size increases, pore shape and pore size changes. The result is a decrease in the porosity after sintering. The fabrication process for ceramics involves several different steps. The first step in ceramics processing is compaction. In the compaction stage, ceramic powders are pressed in a die to shape the powder into the desired form. Sintering is one of the final stages of ceramics fabrication and is used to increase the strength of the compacted material. In the Sintering of Ceramics section,

Read More...

How to Measure Phase Distribution and Degree of Sintering in Iron Ore Pellets

by

Abstract

Iron ore pellets are made from refined and ground ore that is balled into spheroids and then heat treated. Pellet properties are measured through standardized physical, chemical and metallurgical tests to guarantee a high quality end product. However to better understand the oxidation and sintering of iron ore pellets one has to study the microstructures. This paper provides a proof of concept that optical microscopy combined with image analysis methods can be used to quantitatively measure phase distribution and degree of sintering in iron ore pellets.

I. INTRODUCTION

The iron ore extracted from LKAB’s underground mines consists mainly of the mineral magnetite. Magnetite, as the name implies is the most magnetic of all the naturally occurring minerals and has a black color with a brownish tint. About 80% of LKAB production consists of iron ore pellets, which are are made from...

Read More...

Particle Packing, Compaction And Sintering In Powder Metallurgy

by

This thesis focuses on the improvement of density based on the controlhg of particle packing and the subsequent densification processes. Fist, the two-sphere mode1 for monosized powder to determine the lattice diffiision contribution in sintering is considered. Based on Eadie's model, two new solutions are developed and presented, an upper lirnit solution with dace curvature at a maximum al1 dong the neck and a more accurate solution in which the form of the surface curvature at the neck can be varied as appropriate. Producing birnodal powder distribution powder metallurgy (Pl4 parts is next considered. It is shown that this technique is capable of producing parts with exceilent final densities and mechanical properties. In order to explain the above expenrnental results, theoretical research about bimodal powder is focused on particle packing. The first theoretical tool is the coordination number of the particles a...

Read More...

Tribological Behavior And Characteristics Of Sintered Iron Based Alloys

by

SUMMARY

Using conventional PM technologies a new iron based antifriction material containing Cu, Sn, Pb and MoS2 has been developed in order to meet specific working conditions. The compacted samples were sintered in different conditions in dry hydrogen 8 and the effect of the powder additions on the mechanical characteristics was evaluated. The tribological behavior of the different iron based materials has been studied by pin on disc tests and the coefficient of friction and wear rate have been analyzed in order to identify the effect of base material composition. Also, the microstructure of the wear surface was investigated.

Read More...
Translate »
s2Member®