Synthesis of VN-Reinforced Iron-Based Composite

2012 ◽  
Vol 557-559 ◽  
pp. 240-243 ◽  
Author(s):  
Shi Ping Zhang
Keyword(s):  
In Situ Synthesis ◽  
Synthesis Process ◽  
Homogeneous Distribution ◽  
Vanadium Nitride ◽  
X Ray Diffraction ◽  
Nitrogen Gas ◽  
X Ray ◽  
Fine Size ◽  
Particulate Reinforced

Vanadium nitride (VN) particulate reinforced Fe-based composite was produced with ferrovanadium, Ferromolybdenum, ferrochromium and nitrogen gas by in situ synthesis process. The microstructure of the composites was characterized by X-ray diffraction and scanning electron microscopy. With the help of differential thermal analysis, reaction process of Fe-V-N system was discussed. The results show that the composite consists of VN and α-Fe phase. VN particles exhibit fine size and homogeneous distribution in Fe matrix. Formation of VN at 674°C is due to the reaction between ferrovanadium and nitrogen gas.

Grain Refinement of AZ91D Magnesium Alloy by In Situ Al4C3 Particles

2011 ◽  
Vol 306-307 ◽  
pp. 429-432
Author(s):  
Hui Han ◽  
Hua Ming Miao ◽  
Sheng Fa Liu ◽  
Yang Chen
Keyword(s):  
Magnesium Alloy ◽  
Grain Refinement ◽  
Synthesis Process ◽  
X Ray Diffraction ◽  
X Ray ◽  
Az91d Magnesium Alloy ◽  
Average Grain Size ◽  
Central Regions ◽  
Heterogeneous Nucleus

Experiments were conducted to fabricate the Al4C3 particles by powder in-situ synthesis process under argon atmosphere and examine the grain refinement of AZ91D magnesium alloy with the addition of 0.6%Al4C3(hereafter in mass fraction,%). By means of X-ray diffraction (XRD), scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDS), the results show the successful fabrication of Al4C3 particles. After adding 0.6%Al4C3, the average grain size of AZ91D magnesium alloy decreased from 360μm to 243μm. Based on the differential thermal analysis (DTA) results and calculations of the planar disregistry between Al4C3 and α-Mg, Al4C3 particles located in the central regions of magnesium grains can act as the heterogeneous nucleus of primary α-Mg phase.

Investment Casting of Titanium Matrix Composites

2005 ◽  
Vol 475-479 ◽  
pp. 2551-2554 ◽  
Author(s):  
Si Young Sung ◽  
Keun Chang Park ◽  
Myoung Gyun Kim ◽  
Young Jig Kim
Keyword(s):  
In Situ Synthesis ◽  
Matrix Composites ◽  
Reaction Products ◽  
X Ray Diffraction ◽  
Titanium Matrix ◽  
Titanium Matrix Composites ◽  
X Ray ◽  
Conventional Casting ◽  
Electron Probe Micro Analyzer

The aim of the present work is to investigate the possibility of in-situ synthesis and net-shape of the titanium matrix composites (TMCs) using a casting route. From the scanning electron microscopy (SEM), electron probe micro-analyzer (EPMA), X-ray diffraction (XRD) and thermodynamic calculations, the spherical TiC and needle like TiB reinforced hybrid TMCs could be obtained by the conventional casting route between titanium and B4C. No melts-mold reaction could be possible between (TiC+TiB) hybrid TMCs and the SKKU mold, since the mold is composed of interstitial and substitutional reaction products. Not only the sound in-situ synthesis but also the economic net-shape of TMCs could be possible by conventional casting route.

IN SITU SYNTHESIS, CHARACTERIZATION AND FREQUENCY DEPENDENT AC CONDUCTIVITY OF POLYANILINE/CoFe2O4 NANOCOMPOSITES

2011 ◽  
Vol 01 (03) ◽  
pp. 357-362 ◽  
Author(s):  
G. D. PRASANNA ◽  
H. S. JAYANNA
Keyword(s):  
Ac Conductivity ◽  
Room Temperature ◽  
In Situ Polymerization ◽  
In Situ Synthesis ◽  
Electron Micrograph ◽  
Frequency Range ◽  
X Ray Diffraction ◽  
Scanning Electron Micrograph ◽  
X Ray

The polyaniline (PANI)/ CoFe2O4 nanocomposites were prepared by an In Situ polymerization of aniline in an aqueous solution. The composites were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectrum,thermogravimetric analysis (TGA) and scanning electron micrograph (SEM). The AC conductivity and dielectric properties of these composites were investigated in the frequency range 1 kHz–10 MHz at room temperature. The AC conductivity was found to be constant up to 1 MHz and thereafter it increases steeply and it was observed maximum for the PANI with 60 wt% of CoFe2O4 nanocomposite. At lower frequencies the values of dielectric constant is maximum for pure CoFe2O4 nanoparticles.

In situ Synthesis of Mixed-Valent Manganese Oxide Nanocrystals:  An In situ Synchrotron X-ray Diffraction Study

2006 ◽  
Vol 128 (14) ◽  
pp. 4570-4571 ◽  
Author(s):  
Xiong-Fei Shen ◽  
Yun-Shuang Ding ◽  
Jonathan C. Hanson ◽  
Mark Aindow ◽  
Steven L. Suib
Keyword(s):  
Manganese Oxide ◽  
Diffraction Study ◽  
In Situ Synthesis ◽  
X Ray Diffraction ◽  
X Ray

Study on Microstructure of Vanadium and Chromium-Carbide Reinforced Fe Matrix Surface Composite

2011 ◽  
Vol 399-401 ◽  
pp. 425-429
Author(s):  
Jing Wang ◽  
Si Jing Fu ◽  
Yi Chao Ding ◽  
Yi San Wang
Keyword(s):  
Chromium Carbide ◽  
In Situ Synthesis ◽  
X Ray Diffraction ◽  
Iron Matrix ◽  
X Ray ◽  
Surface Composite ◽  
Matrix Surface ◽  
Scanning Electron ◽  
Cast Technique

Vanadium and chromium-carbide particulates reinforced iron matrix surface composite was produced by cast technique and in-situ synthesis technique. The microstructure of the surface composite was studied by scanning electron microscope(SEM) and X-ray diffraction(XRD). The results show that the production of an iron matrix surface composite reinforced by vanadium and chromium-carbide particulates using the process is feasible. Spherical VC particles and strip-chunky Cr7C3 are generated in the surface composite. An excellent metallurgy-bond is observed between the surface composite and the mater-steel.

Microstructure Evolution of In Situ Synthesized VC Reinforced Iron Matrix Composites

2012 ◽  
Vol 217-219 ◽  
pp. 71-74
Author(s):  
Jing Wang ◽  
Si Jing Fu ◽  
Shu Yong Jiang ◽  
Hong Cheng
Keyword(s):  
Electron Microscopy ◽  
In Situ Synthesis ◽  
Matrix Composites ◽  
X Ray Diffraction ◽  
Iron Matrix ◽  
X Ray ◽  
Matrix Microstructure ◽  
The Matrix ◽  
Scanning Electron

Iron matrix composite reinforced with VC reinforcements was produced by in situ synthesis technique. The microstructure of the composites was characterized by X-ray diffraction and scanning electron microscopy. The micrographs revealed the morphology and distribution of the reinforcements. The results show that the composite consists of VC carbide as the reinforcing phase and α-Fe as the matrix. The distribution of spherical VC particulates in iron matrix is uniform, and the matrix microstructure of Fe-VC composite is pearlite.

An investigation into the temperature phase transitions of synthesized materials with Al- and Mg-doped lithium manganese oxide spinels by in situ powder X-ray diffraction

2016 ◽  
Vol 32 (1) ◽  
pp. 23-30
Author(s):  
C. D. Snyders ◽  
E. E. Ferg ◽  
D. Billing
Keyword(s):  
Phase Transitions ◽  
Intermediate Phase ◽  
Phase Changes ◽  
Synthesis Process ◽  
Temperature Phase ◽  
Gravimetric Analysis ◽  
Spinel Oxide ◽  
X Ray Diffraction ◽  
X Ray

Three spinel materials were prepared and characterized by in situ powder X-ray diffraction (PXRD) techniques to track their phase changes that occurred in the typical batch synthesis process from a sol–gel mixture to the final crystalline spinel oxide. The materials were also characterized by thermal gravimetric analysis, whereby the materials decomposition mechanisms that were observed as the precursor, was gradually heated to the final oxide. The results showed that all the materials achieved their total weight loss at about 400 °C. The in situ PXRD analysis showed the progression of the phase transitions where certain of the materials changed from a crystalline precursor to an amorphous intermediate phase and finally to the spinel cathode oxide (Li1.03Mg0.2Mn1.77O4). For other materials, the precursor would start as an amorphous phase and upon heating, convert into an impure intermediate phase (Mn2O3) before forming the final spinel oxide (Li1.03Mn1.97O4). On the other hand, the LiAl0.4Mn1.6O4 would start with an amorphous precursor, with no intermediate phases and immediately formed the final spinel oxide phase. The in situ PXRD study also showed the increases in the materials respective lattice parameters of the crystalline unit cells upon heating and the significant increases in their crystallite sizes when heated above 600 °C.

In-Situ Study of Dynamic Structural Rearrangements During Stress Relaxation

1994 ◽  
Vol 38 ◽  
pp. 243-254 ◽  
Author(s):  
A. D. Westwood ◽  
C. E. Murray ◽  
I. C. Noyan
Keyword(s):  
Stress Relaxation ◽  
Structural Changes ◽  
Applied Strain ◽  
Homogeneous Distribution ◽  
Structural Rearrangements ◽  
X Ray Diffraction ◽  
X Ray ◽  
In Situ Study ◽  
Elastic Strains

Abstract We have conducted in-situ, real-time x-ray diffraction experiments to probe the dynamic structural changes occurring in copper during loading and then on relaxation. The 331 KαI, KαII peaks were used to monitor the development of elastic strains during loading, and their response during relaxation. The peak width was studied to better understand the structural changes that occur during loading, and more importantly on relaxation, since it is these structural rearrangements that reduce the overall strain in the system and allow the stress to relax. The results revealed that the structure is highly mobile immediately following the start of stress relaxation. The mobility decreases with time, scales with the magnitude of the applied strain and is highly dependent upon the applied strain rate. In addition, it was apparent that the KαI and KαII peaks do not respond in the same way to the elastic strains and that they also show different structural rearrangements. This suggests an in homogeneous distribution of displacements within the sample.

Production and Microstructure of In Situ Synthesized (Ti,W)C Reinforced Iron Matrix Composite

2012 ◽  
Vol 457-458 ◽  
pp. 7-10 ◽  
Author(s):  
Jing Wang ◽  
Si Jing Fu ◽  
Yuan Hui Li
Keyword(s):  
Matrix Composite ◽  
In Situ Synthesis ◽  
Scanning Electron Micrographs ◽  
Matrix Interface ◽  
Powder Metallurgy Technique ◽  
X Ray Diffraction ◽  
Iron Matrix ◽  
X Ray ◽  
Scanning Electron

A powder metallurgy technique combined with in-situ synthesis technique was applied to produce (Ti,W)C particulates reinforced iron matrix composite. The sintered composites were characterized by X-ray diffraction and scanning electron microscopy. (Ti,W)C and α-Fe were detected by X-ray diffraction analysis. The scanning electron micrographs revealed the morphology and distribution of the reinforcements. The results show that the rectangular (Ti,W)C carbides are distributed uniformly in the composite. The (Ti,W)C/Fe matrix interface is found to be free from cracks and deleterious phases. The reasons for the formation of coarse (Ti,W)C particles were also discussed .

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