scholarly journals Microstructure and Mechanical Properties of Pressure-Quenched SS304 Stainless Steel

Materials ◽  
2019 ◽  
Vol 12 (2) ◽  
pp. 290 ◽  
Author(s):  
Peng Wang ◽  
Yang Zhang ◽  
Dongli Yu
Keyword(s):  
High Pressure ◽  
Metallographic Analysis ◽  
Polycrystalline Materials ◽  
Test Results ◽  
X Ray Diffraction ◽  
X Ray ◽  
Self Heating ◽  
Density Of Dislocations ◽  
Transmission Electron ◽  
Quenching Method

Bulk SS304 polycrystalline materials with ultrafine microstructures were prepared via a high-pressure self-heating melting and quenching method. Analyses of phase composition, grain size and microstructure were performed using metallographic analysis, X-ray diffraction, Rietveld refinement and transmission electron microscope (TEM). The effects of pressure and cooling rate on the solidification of SS304 were analyzed. Mechanical property test results show that, compared with the as-received sample, the hardness and the yield strength of the pressure-quenched (PQ) samples were greatly increased, the ultimate tensile strength changed minimally, and the elongation rate became small, primarily due to the large density of dislocations in the sample. The high-pressure self-heating melting and quenching method is an exotic route to process a small piece of steel with moderate properties and ultrafine microstructure.

Fabrication and Microstructure of Ge-Sb-S-CsCl Chalcogenide Glass Containing β-GeS2 Nanocrystals

2014 ◽  
Vol 665 ◽  
pp. 119-123
Author(s):  
Ji Yan Hao ◽  
Hai Tao Liu
Keyword(s):  
Chalcogenide Glass ◽  
Spherical Shape ◽  
Orthorhombic Phase ◽  
Far Infrared ◽  
X Ray Diffraction ◽  
Base Glass ◽  
X Ray ◽  
Transmission Electron ◽  
Infrared Spectral ◽  
Quenching Method

we report the fabrication and microstructure of Ge-Sb-S-CsCl chalcogenide glass containing β-GeS2 nanocrystals. A Ge-Sb-S-CsCl chalcogenide base glass with the better crystalline ability is first fabricated by melt-quenching method, and a further careful thermal process has led to the formation of β-GeS2 nanocrystals in the glass. Transmission electron microscopy showed that the size of β-GeS2 nanocrystals with nearly monodisperse spherical shape ranges from 30 to 45 nm in the glass. Powder X-ray diffraction results confirm that the β-GeS2 nanocrystals are of high crystallization with orthorhombic phase. Energy dispersive spectroscopy is employed for the information of nanocrystals glass composition. It is worthwhile to note that the obtained Ge-Sb-S-CsCl chalcogenide glass containing β-GeS2 nanocrystals still keeps higher transmittance in mid- and far- infrared spectral region.

Microstructural analysis of high-pressure compressed C60

2001 ◽  
Vol 16 (7) ◽  
pp. 1960-1966 ◽  
Author(s):  
K. Miyazawa ◽  
H. Satsuki ◽  
M. Kuwabara ◽  
M. Akaishi
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
High Pressure ◽  
High Resolution ◽  
Microstructural Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Hardness Tests ◽  
Lattice Planes

The structure and hardness of C60 bulk specimens compressed under 5.5 GPa at room temperature to 600 °C are investigated by high-resolution transmission electron microscopy, x-ray diffraction, and micro-Vickers hardness tests. A strong accumulation of the [1 1 0]tr orientation of high-pressure-treated C60 specimens was developed along the compression axis, and stacking faults and nano-sized deformation twins were introduced into the C60 specimens compressed at 450–600 °C. Curved lattice planes indicating a polymerization of C60 were observed by high resolution transmission electron microscopy (HRTEM). The polymerization of the high-pressure-compressed C60 is also supported by the computer simulation of HRTEM images.

Characterizing high-pressure compressed C60 whiskers and C60 powder

2003 ◽  
Vol 18 (1) ◽  
pp. 166-172 ◽  
Author(s):  
Kun'ichi Miyazawa ◽  
Minoru Akaishi ◽  
Yusuke Kuwasaki ◽  
Tadatomo Suga
Keyword(s):  
High Pressure ◽  
Electrical Resistivity ◽  
Electrical Properties ◽  
Vickers Hardness ◽  
High Density ◽  
X Ray Diffraction ◽  
X Ray ◽  
Density Of Dislocations ◽  
Mechanical And Electrical Properties

Structural, mechanical, and electrical properties were examined for C60 whiskers, high-pressure sintered C60 whiskers, and C60 powder. A high density of dislocations was observed in the C60 whiskers, and the C60 whiskers with diameters of a few hundred nanometers were found to be flexible. Although both the specimens sintered under the same condition showed similar surface x-ray diffraction profiles with a strong accumulation of [110]tr orientation, the sintered C60 whiskers showed a higher micro-Vickers hardness and an electrical resistivity four orders of magnitude lower than that of the sintered C60 powder.

Tem Structure Investigations of Low-Temperature MBE Grown Inalas Layers on INP Substrate

1992 ◽  
Vol 263 ◽  
Author(s):  
P. Werner ◽  
Z. Liliental-Weber ◽  
K.M. Yu ◽  
E.R. Weber ◽  
Z. Rek ◽  
...  
Keyword(s):  
Electrical Resistance ◽  
Stacking Faults ◽  
X Ray Diffraction ◽  
Real Crystal ◽  
X Ray ◽  
Group Iii ◽  
Temperature Range ◽  
Density Of Dislocations ◽  
Transmission Electron ◽  
Structure Investigations

ABSTRACTThe real crystal structure of In0.52A10.48As layers grown on InP<001> substrate as a function of the growth temperature (between 150°C and 450°C) was investigated. The following structural / electrical analyses were applied to the samples: transmission electron microscopy (TEM), x-ray diffraction and particle induced x-ray emission (PIXE). In the temperature range between 200°C and 450°C good epitaxial growth of InAlAs layers can be achieved with a low density of dislocations and stacking faults. Ordering of group-III elements on {111} planes was observed for these layers. Structure models of such ordered domains are discussed. At growth temperatures below 300 °C additional As (≈2%) is incorporated in the lattice. Growth at temperatures below 200°C leads to the formation of pyramidal defects with As grains in their cores. As-grown as well as annealed InAlAs layers show a nearly constant, high electrical resistance (106-107Ωcm) in the whole temperature range.

Research on the Microstructure and Mechanical Properties of Spray-Deposited 8009 Heat Resistant Aluminum Alloy

2014 ◽  
Vol 543-547 ◽  
pp. 3733-3736
Author(s):  
Rong Hua Zhang ◽  
Biao Wu ◽  
Xiao Ping Zheng
Keyword(s):  
Mechanical Properties ◽  
Aluminum Alloy ◽  
Tensile Tests ◽  
Test Results ◽  
Secondary Phases ◽  
X Ray Diffraction ◽  
X Ray ◽  
Heat Resistant ◽  
Microstructure And Mechanical Properties ◽  
Transmission Electron

In this study, 8009 heat resistant aluminum alloy was synthesized by the spray atomization and deposition technique. The microstructure and mechanical properties of the alloy were studied using transmission electron microscopy, X-ray diffraction, and tensile tests. The secondary phases in the microstructure of the spray-deposited alloy were examined. The tensile test results indicate that the spray-deposited 8009 alloy both at room and elevated temperature displays superior tensile strength due to the presence of the thermally stable Al12(Fe,V)3Si particles.

Structures and phase transitions of B-Ta2O5 and Z-Ta2O5: two high-pressure forms of Ta2O5

2000 ◽  
Vol 56 (4) ◽  
pp. 659-665 ◽  
Author(s):  
I. P. Zibrov ◽  
V. P. Filonenko ◽  
M. Sundberg ◽  
P.-E. Werner
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
High Pressure ◽  
Rietveld Method ◽  
High Pressure Chamber ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
Transmission Electron ◽  
Heat Treated

A sample of Ta2O5, ditantalum pentaoxide, heat-treated in a `toroid'-type high-pressure chamber at P = 8 GPa and T = 1470 K, was studied by X-ray powder diffraction and high-resolution transmission electron microscopy (HRTEM). Two high-pressure modifications of Ta2O5, isostructural with B-Nb2O5 and Z-Nb2O5, were identified from the X-ray powder pattern. Both structures were refined by the Rietveld method from the X-ray diffraction data: B-Ta2O5, a = 12.7853 (4), b = 4.8537 (1), c = 5.5276 (2) Å, β = 104.264 (2)°, V = 332.45 Å3, Z = 4, space group C2/c; Z-Ta2O5, a = 5.2252 (1), b = 4.6991 (1), c = 5.8534 (1) Å, β = 108.200 (2)°, V = 136.53 Å3, Z = 2, space group C2. The Z-Ta2O5 modification is new. The Ta atoms are six-coordinated in B-Ta2O5 and seven-coordinated in Z-Ta2O5. The two structures are closely related, which makes an intergrowth and a transformation between them possible. An idealized model of the intergrowth structure has been given. The HRTEM study showed defect-rich B-Ta2O5 crystals, which could be interpreted as an intergrowth between the B-Ta2O5 and Z-Ta2O5 phases.

The Microstructure Evolution of AA7050 in the Process of Homogenization

2014 ◽  
Vol 633 ◽  
pp. 173-178
Author(s):  
Zhen Hua Geng ◽  
Kai Li ◽  
Ping Wu
Keyword(s):  
Electron Probe ◽  
Eutectic Phase ◽  
Metallographic Analysis ◽  
Test Results ◽  
X Ray Diffraction ◽  
High Melting Point ◽  
Electron Probe Analysis ◽  
X Ray ◽  
Homogenization Scheme ◽  
Melting Point Eutectic

This paper used the metallographic analysis, X-ray diffraction analysis (XRD), differential scanning thermal analysis (DSC), scanning electron microscope (SEM) and electron probe analysis (EPMA) system to research the evolution law of the microstructure and properties of AA7050 under different homogenization system. And analyzes the cause of this evolution combined with the test results put forward. The research shows that high melting point eutectic phase S (Al2CuMg) can be fully re-dissolution through two-stage homogenization, at the same time avoid the overburning of low melting eutectic phase. We optimized the AA7050 homogenization heat treatment system and the optimal homogenization scheme is 430°C/18h+467°C/12h.

Superhard B–C–N materials synthesized in nanostructured bulks

2002 ◽  
Vol 17 (12) ◽  
pp. 3139-3145 ◽  
Author(s):  
Y. Zhao ◽  
D. W. He ◽  
L. L. Daemen ◽  
T. D. Shen ◽  
R. B. Schwarz ◽  
...  
Keyword(s):  
High Pressure ◽  
Indentation Hardness ◽  
X Ray Diffraction ◽  
X Ray ◽  
Amorphous Phases ◽  
Transmission Electron ◽  
Pressure Synthesis ◽  
Nanocrystalline Composite ◽  
Electron Energy Loss ◽  
Electron Energy Loss Spectra

We report here the high-pressure synthesis of well-sintered millimeter-sized bulks of superhard BC2N and BC4N materials in the form of a nanocrystalline composite with diamond-like amorphous carbon grain boundaries. The nanostructured superhard B–C–N material bulks were synthesized under high P–T conditions from amorphous phases of the ball-milled molar mixtures. The synthetic B–C–N samples were characterized by synchrotron x-ray diffraction, high-resolution transmission electron microscope, electron energy-loss spectra, and indentation hardness measurements. These new high-pressure phases of B–C–N compound have extreme hardnesses, second only to diamond. Comparative studies of the high P–T synthetic products of BC2N, BC4N, and segregated phases of diamond + cBN composite confirm the existence of the single B–C–N ternary phases.

X-ray diffraction and transmission-electron microscopy of natural polycrystalline graphite recovered from high pressure

1994 ◽  
Vol 49 (1) ◽  
pp. 22-27 ◽  
Author(s):  
Shoichi Endo ◽  
Naoki Idani ◽  
Ryuichiro Oshima ◽  
Kaoru J. Takano ◽  
Masao Wakatsuki
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
High Pressure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Polycrystalline Graphite ◽  
Transmission Electron

Effect of HPHT processing on the structure, and thermoelectric properties of Co4Sb12 co-doped with Te and Sn

2015 ◽  
Vol 3 (8) ◽  
pp. 4637-4641 ◽  
Author(s):  
Hairui Sun ◽  
Xiaopeng Jia ◽  
Le Deng ◽  
Pin Lv ◽  
Xin Guo ◽  
...  
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Thermoelectric Properties ◽  
Polycrystalline Materials ◽  
X Ray Diffraction ◽  
X Ray ◽  
Temperature Method ◽  
Co Doped

Te–Sn co-doped Co4Sb12 bulk polycrystalline materials Co4Sb11.7−xTexSn0.3 have been prepared using a high pressure and high temperature method and then characterized using X-ray diffraction.

Sign in / Sign up

Export Citation Format

Share Document