Reduction of Oxide Mixtures for the Production of Sinterable Ceramic Composite Powder Mixture

1994 ◽  
pp. 479-482
Author(s):  
Animesh Jha ◽  
Su Jong Yoon
Keyword(s):  
Powder Mixture ◽  
Ceramic Composite ◽  
Composite Powder

Technology and Properties of Ferroelectromagnetic Lead–Free BFN–Ferrite Composites

2013 ◽  
Vol 58 (4) ◽  
pp. 1405-1409 ◽  
Author(s):  
D. Bochenek ◽  
P. Niemiec
Keyword(s):  
Magnetic Properties ◽  
Ceramic Composite ◽  
Composite Powder ◽  
Barium Carbonate ◽  
Lead Free ◽  
Relaxation Phenomena ◽  
Lead Free Ceramic ◽  
Calcination Method ◽  
Ferrite Composites

Abstract A lead free ceramic composite 0.9BaFe0:5Nb0:5O3-0.1Ni0:5Zn0:5Fe2O4 (BFN-NZF) with ferroelectromagnetic properties have been obtained in presented work. Ceramic composite powder obtained from the simple oxides Fe2O3, Nb2O5, ZnO, NiO and barium carbonate BaCO3. The composition of the composite was chosen so that the ratio of the BFN and NZF components was 90:10. The synthesis of components of BFN-NZF composite was performed using the calcination method. Final densification of synthesized powder has been done using free sintering. The XRD, the microstructure, EDS and dielectric investigations were performed. For comparison of the BFN ceramic and the BFN-NZF composites, temperature and frequency impedance research was conducted. Relaxation phenomena were observed at temperatures above 235°C in the BFN ceramic and above 150°C in the BFN-NZF composite. Obtained results show the coexistence of ferroelectric and magnetic properties. Such properties of obtained composites give the possibility to use them in magnetoelectric transducers.

FORMATION OF TiN/TiB2/TiAl NANO-COMPOSITE BY MECHANICAL ALLOYING OF A POWDER MIXTURE OF Ti-Al-BN

2012 ◽  
Vol 05 ◽  
pp. 581-588
Author(s):  
ROUHOLLAH YAZDI ◽  
SEYED FAESHID KASHANI-BOZORG
Keyword(s):  
Mechanical Alloying ◽  
Powder Mixture ◽  
Composite Powder ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
Nano Composite ◽  
X Ray ◽  
Scanning Electron ◽  
Al Matrix ◽  
Milled Product

In this investigation, TiN / TiB 2/ TiAl nano-composite powder was produced by mechanical alloying technique and subsequent heat treatment. A powder mixture of Ti , BN , and Al with a molar ratio of 4:2:1 was milled for up to 70 h. Microstructures were studied and characterized using X-ray diffraction, scanning electron microscopy and energy-dispersive spectroscopy. The results indicated that TiN and TiB 2-based phases were formed in an amorphous Ti ( Al ) matrix after 30 h of ball milling. With progression of the milling, the amorphous Ti ( Al ) solid solution is partially crystallized and the particle size reduced significantly. Subsequent annealing of the milled product at 600 °C for 0.5 h resulted in the transformation of the unstable amorphous Ti ( Al ) to TiAl crystal structure and formation of TiN / TiB 2/ TiAl nano-composite powder.

Fabrication of TiB2-TiC Composites Optimized by Different Amount of Carbon in the Initial Ti-B-C Powder Mixture

2013 ◽  
Vol 315 ◽  
pp. 720-723 ◽  
Author(s):  
Mitra Akhtari Zavareh ◽  
Mohd Hamdi Bin Abdul Shukor ◽  
Reza Rahbari Ghahnavyeh ◽  
Malihah Amiri Roudan ◽  
Mohsen Shafieirad
Keyword(s):  
High Temperature ◽  
Carbon Content ◽  
Chemical Reaction ◽  
Powder Mixture ◽  
Ceramic Composite ◽  
Temperature Synthesis ◽  
Carbon Particles ◽  
High Temperature Synthesis ◽  
Conventional Sintering

Composites of TiC and TiB2 (TiC-TiB2) were prepared by self-propagating high-temperature synthesis (SHS), using compacted reactant different combinations of Ti, C, and B powders. It is very difficult to densify these materials using conventional sintering techniques. It was found that the chemical reaction between the starting Titanium, boron and carbon particles could be completed at 1200°C producing a pure TiB2+TiC ceramic composite. Various carbon content causes the microstructure of the final products was different.

scholarly journals Sintering and composition of a powder mixture of fine Al2O3 and beta-sialon composite made from bauxite

2002 ◽  
Vol 34 (3) ◽  
pp. 215-221 ◽  
Author(s):  
L.I. Nan ◽  
Wang Jun
Keyword(s):  
Relative Density ◽  
Powder Mixture ◽  
Composite Powder ◽  
Powder Mixtures ◽  
Soaking Time

The sintering and composition of samples made of powder mixtures consisting of fine a-AI2O3 powder and beta-Sialon composite powder which was made from bauxite by carbonthermal reduction and nitridation were studied. The proportion of fine a-AI2O3 to beta'-Sialon composite powder in the powder mixture and soaking time give influences on porosity and relative density of the samples sintered at 1600eC. AI2O3, 15R and MgO which was added in 2 wt.% to improve sintering of the sample disappeared in the samples made of single P'-Sialon composite powder. They solubilize into beta-Sialon. In the sample made of a powder mixture consiting of 60 wt.% beta'-Sialon composite to 40 wt.% a-AI2O3 with addition of 2 wt.% MgO, beta'-Sialon, ct-AI2O3 and MgAION coexist after sintering at 1600BC.

Sintering of Hydroxyapatite-Bioglass Ceramics Composite from Submicrometer Powder

2012 ◽  
Vol 622-623 ◽  
pp. 762-766
Author(s):  
Phanlob Chankachang ◽  
Sittiporn Punyanitya ◽  
Anirut Raksujarit
Keyword(s):  
Mechanical Properties ◽  
Ceramic Composite ◽  
Composite Powder ◽  
Young Modulus ◽  
Human Bone ◽  
Interfacial Stress ◽  
Sintering Aid ◽  
Hydroxyapatite Ceramics ◽  
Hydroxyapatite Composite

The mechanical properties of hydroxyapatite ceramics was improved by adding 5 wt% of Ca-P-Na-based-glass to be as sintering aid and were made their powder to submicron sized. The powders are uniaxially compact and then sintering at 1300°C in air.Microstructure and mechanical properties of the ceramic composite products were investigated. It was found that the strength of hydroxyapatite composite was increased about 42% that of the sample which fabricated by micron sized HA composite powder having the same porosity and this values are in rang of values of the strength of the cortical human bone. Moreover, Young modulus values of 16.4 1.8 GPa matched well with the Young modulus values of human bone, so it will not cause interfacial stress between implant and bone leading to good fixation of the materials.

scholarly journals Peculiarities in mechano-composite structural state based on aluminum for gas detonation sputtering

2017 ◽  
Vol 2 (12) ◽  
pp. 20-25 ◽  
Author(s):  
Александр Ситников ◽  
Alexandr Sitnikov ◽  
Алексей Собачкин ◽  
Aleksey Sobachki ◽  
Владимир Яковлев ◽  
...  
Keyword(s):  
Boron Carbide ◽  
Mechanical Activation ◽  
Powder Mixture ◽  
Composite Powder ◽  
Amorphous State ◽  
Structure Characteristic ◽  
Carbon Powder ◽  
Gas Detonation ◽  
X Ray ◽  
Composite Mixture

Structural peculiarities of a powder composite mixture on the basis of aluminum and dispersion carbon structures intended for gas-detonation sputtering for an anti-friction purpose are investigated in the paper. As initial materials there was used an aluminum powder, carbon powder, boron carbide powder, powder slurry consisting of fullerenes C60 and ultra-dispersion diamonds in a certain ratio. The powder mixture obtained was subjected to a mechanical activation with the aid of a planetary ball mill of AGO-2S type. According to the results of the morphological analysis it was established that a composite mixture possesses a layer structure characteristic for powder mixtures subjected to a mechanical activation in the course of a long period of time. A mean size of obtained mechano-composite particles makes about 100…150 mkm. An X-ray structural investigation of a composite powder mixture formulations 70% Al+30%C+B4C and 70%Al + 30%C60 (total %) + B4C after mechanical activation revealed that boron carbide contributes well to the amorphization of a composite powder mixture. It is also established that after mechano-activation of the “Al+C+B4C” powder mixture during 4 min carbon transforms to an X-ray amorphous state to which testifies the presence of amorphous “halo” at small angles and carbon peaks disappeared completely. There is no carbon dissolution in aluminum and chemical compounds are not formed.

scholarly journals Development of SiC/PVB Composite Powders for Selective Laser Sintering Additive Manufacturing of SiC

Materials ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 2012 ◽  
Author(s):  
Peng Zhou ◽  
Huilin Qi ◽  
Zhenye Zhu ◽  
Huang Qin ◽  
Hui Li ◽  
...  
Keyword(s):  
Additive Manufacturing ◽  
Ceramic Composite ◽  
Composite Powder ◽  
Selective Laser Sintering ◽  
Particle Surface ◽  
Polyvinyl Butyral ◽  
Composite Powders ◽  
Sintering Additive ◽  
Composite Powder Material ◽  
Composite Granules

Subsphaeroidal SiC/polymer composite granules with good flowability for additive manufacturing/3D printing of SiC were prepared by ball milling with surface modification using polyvinyl butyral (PVB). PVB adheres to the particle surface of SiC to form a crosslinked network structure and keeps them combined with each other into light aggregates. The effects of PVB on the shape, size, phase composition, distribution and flowability of the polymer-ceramic composite powder were investigated in detail. Results show that the composite powder material has good laser absorptivity at wavelengths of lower than 500 nm.

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