Carbide Behavior and Micro-void of Inconel 690 According to Nb Content and Aging Temperature

Intermetallic compounds of Dy2Fe16Ga1−xNbx (x = 0.0 to 1.00) were synthesized by arc melting. Samples were investigated for structural, magnetic, and hyperfine properties using X-ray diffraction, vibration sample magnetometer, and Mossbauer spectrometer, respectively. The Rietveld analysis of room temperature X-ray diffraction data shows that all the samples were crystallized in Th2Fe17 structure. The unit cell volume of alloys increased linearly with an increase in Nb content. The maximum Curie temperature Tc ~523 K for x = 0.6 sample is higher than Tc = 153 K of Dy2Fe17. The saturation magnetization decreased linearly with increasing Nb content from 61.57 emu/g for x = 0.0 to 42.46 emu/g for x = 1.0. The Mössbauer spectra and Rietveld analysis showed a small amount of DyFe3 and NbFe2 secondary phases at x = 1.0. The hyperfine field of Dy2Fe16Ga1−xNbx decreased while the isomer shift values increased with the Nb content. The observed increase in isomer shift may have resulted from the decrease in s electron density due to the unit cell volume expansion. The substantial increase in Tc of thus prepared intermetallic compounds is expected to have implications in magnets used for high-temperature applications.

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Microstructures and Properties of Ti-Nb Alloys Produced by Powder Metallurgy

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.80-81.431 ◽

2011 ◽

Vol 80-81 ◽

pp. 431-435 ◽

Cited By ~ 4

Author(s):

Zheng Cun Zhou ◽

J. Du ◽

H. Yang ◽

S.Y. Gu ◽

Y.J. Yan

Keyword(s):

Powder Metallurgy ◽

Testing Machine ◽

Optical Microscope ◽

Mechanical Analysis ◽

Sintered Alloy ◽

Xrd Diffraction ◽

Β Phase ◽

Ω Phase ◽

Nb Content ◽

And Storage

Ti-Nb alloys were prepared by powder metallurgy. Their microstructures are detected by the XRD diffraction and are observed using an optical microscope. The mechanical properties are tested using a dynamic mechanical analysis (DMA) Q800 from TA Instruments in single cantilever mode and using a 100 KN MTS testing machine with control software. It has been found that the sintered Ti-Nb alloys possess the stable α and β phases and the amount in β phase increases with increasing Nb content. The water quenched Ti-35.4Nb alloy contains α,,and βM. The as-sintered alloy has higher yield stress and storage modulus than the water quenched Ti-35.4Nb alloy, which is resulted from the α phase with high modulus in the as-sintered alloy. The ω phase can be precipitated from βMwhen the water quenched Ti-35.4Nb alloy is aged at 300 °C, causing the modulus to increase since ω phase has large modulus.

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Effect of Lipase Activity and Aging Temperature on Formation of Ethyl Fatty Acieds in Miso.

journal of the japanese society for cold preservation of food ◽

10.5891/jafps1987.20.4_175 ◽

1994 ◽

Vol 20 (4) ◽

pp. 175-180

Author(s):

Mitsuaki KATAGIRI ◽

Sumio SHIMIZU

Keyword(s):

Lipase Activity ◽

Aging Temperature

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The effects of Nb content on microstructure and fracture behavior of near α titanium alloys

Materials & Design (1980-2015) ◽

10.1016/j.matdes.2014.10.069 ◽

2015 ◽

Vol 66 ◽

pp. 267-273 ◽

Cited By ~ 23

Author(s):

Binguo Fu ◽

Hongwei Wang ◽

Chunming Zou ◽

Zunjie Wei

Keyword(s):

Titanium Alloys ◽

Fracture Behavior ◽

Nb Content

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EFFECTS OF A PARTIAL SUBSTITUTION OF Cu ELEMENTS BY Nb ELEMENTS IN YBaCuO SYSTEM

Modern Physics Letters B ◽

10.1142/s021798499000101x ◽

1990 ◽

Vol 04 (12) ◽

pp. 823-830 ◽

Cited By ~ 6

Author(s):

S. HIGO ◽

Y. HAKURAKU ◽

T. OGUSHI ◽

I. KAWANO ◽

Y. ISHIKAWA

Keyword(s):

Solid State Reaction Method ◽

Lattice Parameter ◽

Partial Substitution ◽

Maximum Temperature ◽

X Ray ◽

Cubic Lattice ◽

Nb Content ◽

Molecular Ratios ◽

Diffraction Patterns ◽

Two Phases

Samples of the YBaCuNbO system with different molecular ratios of YBa 2 NbO y to YBa 2 Cu 3 O 7−d, were prepared in air by the solid-state reaction method. The X-ray powder diffraction patterns showed that the sample was composed of two phases, one corresponding to the YBa 2 Cu 3 O 7−d phase and the other to the YBa 2 NbO y phase with a cubic lattice parameter of 8.425 Å to 8.436 Å depending on the Nb content. The superconducting zero resistivity temperature, T c 0, of the YBaCuNbO system increased with the increase of the molecular ratios, from 91.2 K up to a maximum temperature of 92.8 K, and then, by a further increase in the molecular ratio, the T c 0 was drastically reduced with a gradient of −1.94 K /%x.

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Microstructure Characteristics in Continuous Cooling Transformation of an Nb Microalloyed Steel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.228-229.72 ◽

2011 ◽

Vol 228-229 ◽

pp. 72-76

Author(s):

J. H. Yang ◽

Q. Y. Liu

Keyword(s):

Microalloyed Steel ◽

Controlled Rolling ◽

Controlled Cooling ◽

Cooling Rates ◽

Continuous Cooling Transformation ◽

Microstructure Characteristics ◽

Continuous Cooling ◽

Nb Content ◽

Nb Microalloyed Steel ◽

Two Stages

Deformation dilatometry has been used to simulate controlled hot rolling followed by controlled cooling of a Nb microalloyed pipeline steels, the microstructure and transformation characteristics in the steel and the effect of deformation on transformation are studied. According to the results of both dilatometry measurements and microstructure observations, the continuous cooling transformation curves (CCT) of the tested steels are constructed. The results show that Nb content and deformation enhance the formation of acicular ferrite; the microstructure of the steel range from PF, QF to AF with increasing of cooling rates from 0.5 to 50°C /s in a two stages controlled rolling and the microstructure revolution is sensitive to cooling rates when it is lower than 5°C /s, however, when the cooling rate increasing further, the microstructure didn’t change very much but M/A constituents in matrix is refined and dispersed.

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