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71.
Electrodeionization (EDI) of cesium from cesium-sorbed ammonium molybdophosphate-polyacrylonitrile (AMP-PAN) was investigated by passing eluant through the packed bed of ion-exchange resin in an electrodialysis cell. The deionized cesium from the packed bed was recovered in catholyte by migration and in the eluant by convection. Recovery percentage of Cs by migration increased while the recovery by convection decreased with increase in current density from 20 to 40 mA/cm2. Increased eluant concentration resulted in low migration percentage of cesium. Increased catholyte concentration had a negligible effect on total recovery. Apparent diffusion coefficients evaluated using the Nernst–Plank relation increased with increase in current density and catholyte concentration while a decreasing trend was observed with increase in eluant concentration. 相似文献
72.
G. M. Karthik P. Mastanaiah G. D. Janaki Ram Ravi Sankar Kottada 《Metallurgical and Materials Transactions B》2017,48(3):1416-1422
This work offers a fresh perspective on buttering, a technique often considered for fusion welding of dissimilar metals. For the first time, buttering was attempted in solid state using friction deposition. Using this new “friction buttering” technique, fusion welding of two different dissimilar metal pairs (austenitic stainless steel/borated stainless steel and Al-Cu-Mg/Al-Zn-Mg-Cu) was successfully demonstrated. The results show that friction buttering can simplify a tough dissimilar welding problem into a routine fusion welding task. 相似文献
73.
Pillai Mohan Aswathy Jayakumari Babu Anooja Upendran Syamaprasad 《Journal of the American Ceramic Society》2013,96(4):1176-1180
Polycrystalline samples of NdFeAsO1?xFx (Nd1111) with x = 0, 0.1, 0.2, 0.3, and 0.4 were synthesized using a solid‐state method at ambient pressures. A maximum transition temperature (TC) of 52.0 K and a JC of 1050 A/cm2 at 12 K were observed for x = 0.3 and 0.4, respectively. The transport and magnetic properties observed for each stoichiometry have remarkable correlation with their corresponding structural and microstructural aspects. Moreover, the superconducting properties exhibited in this material, processed at a relatively low temperature of 1000°C, are competitive as compared to the existing reports wherein high pressures/temperatures are inevitable. 相似文献
74.
Xinghua Yu Jeremy L. Caron S. S. Babu John C. Lippold Dieter Isheim David N. Seidman 《Metallurgical and Materials Transactions A》2011,42(12):3669-3679
BlastAlloy 160 (BA160) is a low-carbon martensitic steel strengthened by copper and M2C precipitates. Heat-affected zone (HAZ) microstructure evaluation of BA160 exhibited softening in samples subjected to the
coarse-grained HAZ thermal simulations of this steel. This softening is partially attributed to dissolution of copper precipitates
and metal carbides. After subjecting these coarse-grained HAZs to a second weld thermal cycle below the A
c1 temperature (at which austenite begins to form on heating), recovery of strength was observed. Atom-probe tomography and
microhardness analyses correlated this strength recovery to re-precipitation of copper precipitates and metal carbides. A
continuum model is proposed to rationalize strengthening and softening in the HAZ regions of BlastAlloy 160. 相似文献
75.
76.
Effect of Milling Time on the Microstructure and Thermoelectric Properties of P‐type TAGS‐90 Alloys by HEM and SPS 下载免费PDF全文
Hyo‐Seob Kim Babu Madavali Soon‐Jik Hong Taek‐Soo Kim 《International Journal of Applied Ceramic Technology》2016,13(2):239-244
In this study, p‐type TAGS‐90 powders were fabricated using high‐energy milling (HEM), subsequently sintered by spark plasma sintering (SPS). And then, the effects of milling time on the microstructure, mechanical, and thermoelectric properties were investigated. The powders were quickly decreased to fine particles of ~1 μm in size and uniformly agglomerated with the increasing of milling time. XRD results indicated that all milled powders and SPSed samples showed single GeTe phase. Also, EDX results showed almost no contamination and exact composition after milling. The maximum figure of merit, ZT = 1.08, was obtained for 30‐min‐milled sample at 723 K. 相似文献
77.
Effect of Sintering Temperature on Thermoelectric Properties of p‐Bi2Te3 Alloys Produced by Gas Atomization 下载免费PDF全文
Babu Madavali Hyo‐Seob Kim Min‐Gyu Choi Gi‐Chan Park Jar‐Myung Koo Hyeon‐Taek Son Soon‐Jik Hong 《International Journal of Applied Ceramic Technology》2016,13(2):245-251
In this research, p‐type Bi2Te3–75% Sb2Te3 thermoelectric alloy powders were produced by gas atomization and subsequently sintered by hot pressing at different temperatures. The grain growth of the hot‐pressed samples was observed with increasing sintering temperature from 380°C to 460°C. The compressive strength increased with increasing hot‐pressing temperature due to the high relative density of bulk samples obtained at high temperatures. The effect of sintering temperature on thermoelectric (TE) properties was studied. The maximum power factor 3.48 mW/mK2 was obtained for the sample hot pressed at 420°C due to the resulting high electrical conductivity and enhanced Seebeck coefficient values. 相似文献
78.
B. Rajesh Babu M. S. R. Prasad K. V. Ramesh Y. Purushotham 《Journal of Inorganic and Organometallic Polymers and Materials》2016,26(3):589-597
The effect of Al substitution on electrical and dielectric parameters of Ni–Zn ferrite has been discussed in the present work. The phase identification, surface morphology was studied using X-ray diffractometer (XRD), scanning electron microscope (SEM), respectively. The XRD patterns confirm the single-phase formation of these ferrites. With Al3+, substitution lattice parameter decreases due to smaller Al3+ ions replacing Fe3+ ions. The average grain size obtained from SEM results are in the range of 390–27 nm. The DC resistivity was observed to increase with increasing Al3+ ions concentration due to the unavailability of Fe3+ ions. Dielectric constant (\(\upvarepsilon ^{\prime }\)) and dielectric loss tangent (tan δ) have been studied as a function of frequency (1 kHz–10 MHz) and temperature (50–300 °C). The observed results are explained on the basis of interfacial polarization as predicted by Maxwell and Wagner. 相似文献
79.
D.?Karthik S.?SwaroopEmail author 《Journal of Materials Engineering and Performance》2016,25(7):2642-2650
The objective of this study is to investigate the influence of laser peening without coating (LPwC) on austenitic to martensitic (γ → α′) phase transformation and corrosion behavior of austenitic stainless steel AISI 321 in 3.5% NaCl environment. Results indicate that LPwC induces a large compressive residual stresses of nearly ?854 MPa and γ → α′ phase transformation of about 18% (volume fraction). Microstructures of peened surface confirmed the γ → α′ phase transformation and showed no grain refinement. Hardness increased slightly with a case depth of 900 μm. Despite the smaller surface roughness introduced, corrosion resistance improved after peening due to compressive residual stresses. 相似文献
80.
An experimental study is conducted to evaluate the use of rubber seed oil with diesel at a proportion of 20% by volume (RSO20) in a constant speed (1500?rpm) direct injected four-stroke air-cooled single-cylinder compression ignition engine at different injection timings (24°, 27°, 30°, 33° bTDC (before top dead centre)). A series of tests were conducted at various engine load conditions at the rated power of 5.9?kW. The injection pressure was maintained at 200?bar. As a result of investigations, at the full load condition, the brake thermal efficiency of RSO20 at 30° bTDC is high compared with other injection timings and brake energy fuel consumption is increased when advancing injection timing. There is a significant reduction in unburned hydrocarbon emission and carbon monoxide emission, and the oxides of nitrogen emission (NOx) is increased when advancing the injection timing. 相似文献