scholarly journals Powder Metallurgical Processing and Characterization of Molybdenum Addition to Tungsten Heavy Alloys by Spark Plasma Sintering

Materials ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 5756
Author(s):  
A. Raja Annamalai ◽  
A. Muthuchamy ◽  
Muthe Srikanth ◽  
Senthilnathan Natarajan ◽  
Shashank Acharya ◽  
...  
Keyword(s):  
Spark Plasma Sintering ◽  
Microstructural Characterization ◽  
Tungsten Alloy ◽  
Plasma Sintering ◽  
Heavy Alloys ◽  
Molybdenum Addition ◽  
Spark Plasma ◽  
Iron Nickel ◽  
Heavy Tungsten Alloy ◽  
High Level

The effect of adding molybdenum to the heavy tungsten alloy of W-Ni-Fe on its material characteristics was examined in the current study. The elemental powders of tungsten, iron, nickel, and molybdenum, with a composition analogous to W-3Fe-7Ni-xMo (x = 0, 22.5, 45, 67.5 wt.%), were fabricated using the spark plasma sintering (SPS) technique at a sintering temperature of 1400 °C and under pressure of 50 MPa. The sintered samples were subjected to microstructural characterization and tested for mechanical strength. The smallest grain size of 9.99 microns was observed for the 45W-45Mo alloy. This alloy also gave the highest tensile and yield strengths of 1140 MPa and 763 MPa, respectively. The hardness increased with the increased addition of molybdenum. The high level of hardness was observed for 67.5Mo with a 10.8% increase in the base alloy’s hardness. The investigation resulted in the alloy of 45W-7Ni-3Fe-45Mo, observed to provide optimum mechanical properties among all the analyzed samples.

Microstructural characterization and mechanical behaviours of TiN-graphite composites fabricated by spark plasma sintering

2020 ◽  
Vol 91 ◽  
pp. 105253
Author(s):  
Ojo Jeremiah Akinribide ◽  
Babatunde Abiodun Obadele ◽  
Samuel Olukayode Akinwamide ◽  
Olusola Olaitan Ayeleru ◽  
Mehdi Eizadjou ◽  
...  
Keyword(s):  
Spark Plasma Sintering ◽  
Microstructural Characterization ◽  
Plasma Sintering ◽  
Mechanical Behaviours ◽  
Spark Plasma ◽  
Graphite Composites

93W–5.6Ni–1.4Fe heavy alloys with enhanced performance prepared by cyclic spark plasma sintering

2014 ◽  
Vol 599 ◽  
pp. 233-241 ◽  
Author(s):  
Xiaoqiang Li ◽  
Ke Hu ◽  
Shengguan Qu ◽  
Li Li ◽  
Chao Yang
Keyword(s):  
Spark Plasma Sintering ◽  
Plasma Sintering ◽  
Heavy Alloys ◽  
Spark Plasma

Reactive Sintering of TaB2 Using Spark Plasma Sintering Method

2014 ◽  
Vol 88 ◽  
pp. 54-59 ◽  
Author(s):  
Jolanta Laszkiewicz-Łukasik ◽  
Lucyna Jaworska ◽  
Piotr Putyra ◽  
Barbara Smuk
Keyword(s):  
Spark Plasma Sintering ◽  
High Energy ◽  
Tantalum Powder ◽  
Composition Analysis ◽  
Reactive Sintering ◽  
Boron Powder ◽  
Plasma Sintering ◽  
Spark Plasma ◽  
High Level ◽  
Sintering Method

Tantalum diboride was synthesized and sintered from metallic tantalum powder and amorphous boron powder in one technological process using Spark Plasma Sintering method. The precursors were: tantalum with grain size below 5μm and boron with particle size in the range of 1-2μm. Tantalum powder, before mixing with boron, was subjected to high-energy milling under argon atmosphere in order to reduce specific surface area. The process should be carried out without air, due to protection against the influence of oxygen. During reactive sintering SPS process oxidation participation should be limited because of high exothermic reactions. Morphologies of the powders before and after milling were studied using SEM. Reactive sintering processes were carried out at temperatures from 1800°C up to 2200°C at 48MPa. Sintering duration was in the range of 1-30min. Volume changes of samples and temperature increase during the synthesis were observed and determined. The result of X-Ray phase composition analysis and microstructure observations using SEM are presented. Relative density, Young's modulus, Vickers hardness and fracture toughness of the materials were determined. During the reactive sintering the material of only one phase TaB2, with high level of densification, was obtained.

Microstructural Characterization of Fine-Grained Pb(Zr0.52Ti0.48)O3 Ceramics Fabricated by a Spark Plasma Sintering

2006 ◽  
Vol 317-318 ◽  
pp. 155-158
Author(s):  
Sang Mo Koo ◽  
Seung Hwan Shim ◽  
Jong Won Yoon ◽  
Kwang Bo Shim
Keyword(s):  
Spark Plasma Sintering ◽  
Microstructural Characterization ◽  
Structural Features ◽  
Fine Grained ◽  
Domain Structures ◽  
Plasma Sintering ◽  
Transmission Electron ◽  
Fine Microstructure ◽  
Spark Plasma

The dense Pb(Zr0.52Ti0.48)O3 (PZT) piezoelectric ceramics have been prepared at a low temperature by a spark plasma sintering (SPS) method without excess PbO addition and their structural features including domains were systematically investigated. The fine microstructure consisting of submicrometer-sized grains as well as relative density reaching 99% was achieved by sintering at 950°C which is 400°C lower than that of pressureless sintering (PLS). Transmission electron microscopy (TEM) results confirmed that the sintered specimen contained very dense domain structures inside each grain, showing the nanoscaled single-domains even at the small grains (below 100 nm). The SPS-processed PZT exhibited better piezoelectric properties than those of the PLS-processed one, which is attributed to its fine-microstructural feature.

Microstructural Characterization of In Situ TiB Whiskers in Ti MMCs Fabricated by SPS

2007 ◽  
Vol 336-338 ◽  
pp. 1310-1312
Author(s):  
Hai Bo Feng ◽  
De Chang Jia ◽  
Yu Zhou ◽  
Qing Chang Meng
Keyword(s):  
Electron Microscopy ◽  
Spark Plasma Sintering ◽  
Sintering Temperature ◽  
Microstructural Characterization ◽  
Average Diameter ◽  
Matrix Composites ◽  
Plasma Sintering ◽  
Transmission Electron ◽  
Spark Plasma

The in situ TiB whisker reinforced titanium matrix composites were prepared by mechanical alloying followed by spark plasma sintering. X-ray diffraction, scanning electron microscopy and transmission electron microscopy were used to characterize the microstructure of the TiB whiskers. The effect of sintering temperature on morphologies of in situ TiB whiskers was evaluated. With the increase of spark plasma sintering temperature, the average diameter of in situ TiB whiskers increased. The in situ TiB whiskers exhibited a hexagonal shape with (100), (101) and (10 1 ) planes at the transverse section and a growth orientation of [010]TiB direction.

Effect of doped Lu2O3 on the microstructures and properties of tungsten alloy prepared by spark plasma sintering

2015 ◽  
Vol 456 ◽  
pp. 316-320 ◽  
Author(s):  
Jun Zhang ◽  
Lai-Ma Luo ◽  
Xiao-Yong Zhu ◽  
Hong-Yu Chen ◽  
Jun-Ling Chen ◽  
...  
Keyword(s):  
Spark Plasma Sintering ◽  
Tungsten Alloy ◽  
Plasma Sintering ◽  
Spark Plasma

scholarly journals Synthesis of Dense MgB2 Superconductor via In Situ and Ex Situ Spark Plasma Sintering Method

Materials ◽  
2021 ◽  
Vol 14 (23) ◽  
pp. 7395
Author(s):  
Joseph Longji Dadiel ◽  
Sugali Pavan Kumar Naik ◽  
Paweł Pęczkowski ◽  
Jun Sugiyama ◽  
Hiraku Ogino ◽  
...  
Keyword(s):  
Spark Plasma Sintering ◽  
Microstructural Characterization ◽  
Ex Situ ◽  
Synthesis Methods ◽  
Mgb2 Bulk ◽  
Bulk Superconductors ◽  
Plasma Sintering ◽  
Spark Plasma ◽  
Sintering Conditions

In this study, high-density magnesium diboride (MgB2) bulk superconductors were synthesized by spark plasma sintering (SPS) under pressure to improve the field dependence of the critical current density (Jc-B) in MgB2 bulk superconductors. We investigated the relationship between sintering conditions (temperature and time) and Jc-B using two methods, ex situ (sintering MgB2 synthesized powder) and in situ (reaction sintering of Mg and B powder), respectively. As a result, we found that higher density with suppressed particle growth and suppression of the formation of coarse particles of MgB4 and MgO were found to be effective in improving the Jc-B characteristics. In the ex situ method, the degradation of MgB2 due to pyrolysis was more severe at temperatures higher than 850 °C. The sample that underwent SPS treatment for a short time at 850 °C showed higher density and less impurity phase in the bulk, which improved the Jc-B properties. In addition, the in situ method showed very minimal impurity with a corresponding improvement in density and Jc-B characteristics for the sample optimized at 750 °C. Microstructural characterization and flux pinning (fP) analysis revealed the possibility of refined MgO inclusions and MgB4 phase as new pinning centers, which greatly contributed to the Jc-B properties. The contributions of the sintering conditions on fP for both synthesis methods were analyzed.

Sign in / Sign up

Export Citation Format

Share Document