Degradation Evaluation of HK40 Steel Using Magnetic Properties

2003 ◽  
Vol 17 (08n09) ◽  
pp. 1940-1946
Author(s):  
Seung Hoon Nahm ◽  
Jong Seo Park ◽  
Si Cheon Kim ◽  
Kwon Sang Ryu ◽  
Jeong Min Kim ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Magnetic Susceptibility ◽  
Vickers Hardness ◽  
Room Temperature ◽  
High Reliability ◽  
Tube Steel ◽  
Isothermal Heat Treatment ◽  
Isothermal Heat Treatments ◽  
Heater Tube ◽  
Degradation Evaluation

The effect of isothermal heat treatments, which simulate the microstructural changes observed in furnace heater tube steel at the service temperature, on the magnetic properties was investigated. HK40 steel specimens with five different periods of aging were prepared by an isothermal heat treatment at 1050°C. Magnetic properties such as susceptibility were measured. The magnetic susceptibility at room temperature monotonously increased with the extent of degradation of the material. The Vickers hardness also increased with the extent of degradation. The correlation between the measured magnetic susceptibility and the Vickers hardness was studied. In addition, the applicability of magnetic susceptibility measurements to the evaluation of degraded HK40 steel was discussed. As result, the magnetic susceptibility method could predict the thermal degradation of HK40 steel with high reliability.

Degradation Evaluation of HK-40 Steel Using Electrical Resistivity

2003 ◽  
Vol 17 (08n09) ◽  
pp. 1615-1620 ◽  
Author(s):  
Seung Hoon Nahm ◽  
Kwang Min Yu ◽  
Jong Seo Park ◽  
Young Hyun Nam ◽  
Sang In Han ◽  
...  
Keyword(s):  
Electrical Resistivity ◽  
Material Properties ◽  
Room Temperature ◽  
Creep Damage ◽  
Tube Steel ◽  
Isothermal Heat Treatment ◽  
Resistivity Method ◽  
Electrical Resistivity Method ◽  
Heater Tube ◽  
Degradation Evaluation

More effective nondestructive technology for the estimation on material properties has been sought. In this research, a new electrical resistivity method was attempted for the estimation of the creep damage of a degraded heater tube steel. HK40 steel specimens with five different periods of aging were prepared by an isothermal heat treatment at 1050°C and the electrical resistivity was determined by a standard DC four-point probe method. The electrical resistivity at room temperature monotonously decreased with the extent of degradation of the material. It was also observed that Vickers hardness was correlated with the electrical resistivity. The microstructural changes of material during aging was examined by microscope.

ON THE STRUCTURAL, THERMAL, ELECTRICAL, AND MAGNETIC PROPERTIES OF AuSn

1963 ◽  
Vol 41 (12) ◽  
pp. 2252-2266 ◽  
Author(s):  
J.-P. Jan ◽  
W. B. Pearson ◽  
A. Kjekshus ◽  
S. B. Woods
Keyword(s):  
Thermal Conductivity ◽  
Magnetic Properties ◽  
Electrical Resistivity ◽  
Magnetic Susceptibility ◽  
Air Temperature ◽  
Homogeneity Range ◽  
Room Temperature ◽  
Lattice Constants ◽  
Conduction Electrons ◽  
Electrical And Magnetic Properties

The Au1−xSn phase has a homogeneity range within the limits 50.0 and 50.5 at.% Sn. The lattice constants and observed densities vary between the limits:[Formula: see text]The thermal conductivity, electrical resistivity, and absolute thermoelectric power of oriented single crystals of Au1−xSn have been measured between 2.5° K and room temperature. The results exhibit pronounced anisotropies. Measurements of the magnetic susceptibility between liquid air temperature and 650–750° K are also reported for three different Au1−xSn alloys.The various results are discussed, and some speculations are presented regarding the number of conduction electrons in AuSn.

scholarly journals Copper(II) Halide Salts with 1-(4′-Pyridyl)-Pyridinediium

Inorganics ◽  
2020 ◽  
Vol 8 (3) ◽  
pp. 18 ◽  
Author(s):  
Jeffrey C. Monroe ◽  
Christopher P. Landee ◽  
Melanie Rademeyer ◽  
Mark M. Turnbull
Keyword(s):  
Magnetic Properties ◽  
Magnetic Susceptibility ◽  
Hydrogen Bonding ◽  
Room Temperature ◽  
Crystal Packing ◽  
Monoclinic Space Group ◽  
Antiferromagnetic Exchange ◽  
Temperature Dependent ◽  
Packing Arrangement ◽  
Halide Salts

The compounds [1,4′-bipyridine]-1,1′-diium [CuCl4] (1) and [1,4′-bipyridine]-1,1′-diium [CuBr4] (2) were prepared and their crystal structures and magnetic properties are reported. The compounds are isomorphous and crystallize in the monoclinic space group C2/c. The cation crystallizes in a two-fold disordered fashion with the terminal nitrogen and carbon atoms exhibiting 50% occupancies. This results in a crystal packing arrangement with significant hydrogen bonding that is very similar to that observed in the corresponding 4,4′-bipyridinediium complexes. Temperature dependent magnetic susceptibility measurements and room temperature EPR spectroscopy indicate the presence of very weak antiferromagnetic exchange. The data were fit to the Curie–Weiss law and yielded Weiss constants of −0.26(5) K (1) and −1.0(1) K (2).

scholarly journals Magnetic susceptibility and related properties of rare-earth crystals

1939 ◽  
Vol 170 (940) ◽  
pp. 112-129 ◽  
Keyword(s):  
Magnetic Properties ◽  
Magnetic Susceptibility ◽  
Rare Earth ◽  
Specific Heat ◽  
Absorption Spectra ◽  
Room Temperature ◽  
Magnetic Susceptibilities ◽  
Temperature Range ◽  
The Mean

This paper has arisen from attempts to correlate the results of experiments on magnetic susceptibilities, specific heat and absorption spectra of rareearth crystals. No theory has yet been advanced which is capable of giving simultaneous quantitative numerical agreement on all these properties, nor indeed does it seem possible to develop such a theory. For reasons which we shall explain, it seems more likely that some of the data are wrong, or at least, that they have been wrongly interpreted. Many measurements have been made of the magnetic properties of hydrated rare-earth crystals. Accurate values of the mean molecular susceptibility, X , have been obtained over a temperature range from a few degrees absolute to room temperature, and the anisotropy of the susceptibility at room temperature has also been measured

Magnetic properties of some tridentate Schiff-base-manganese(II) complexes

1971 ◽  
Vol 24 (11) ◽  
pp. 2249 ◽  
Author(s):  
KD Butler ◽  
KS Murray ◽  
BO West
Keyword(s):  
Magnetic Properties ◽  
Magnetic Susceptibility ◽  
Schiff Base ◽  
Anthranilic Acid ◽  
Room Temperature ◽  
Magnetic Moments ◽  
Calculated Data ◽  
Exchange Integral ◽  
X Ray ◽  
Tridentate Schiff Base

A series of manganese(II) chelates of stoicheiometry [MnL] have been synthesized, where LH2 is a dibasic tridenate Schiff base formed between a 5-substituted salicylaldehyde and either a 5-substituted β- hydroxyaniline or anthranilic acid. The complexes are extremely susceptible to oxidation in solution but stable when dry. Some of the complexes were isolated as hemihydrates and others as mixed hydrate- ethanolates. Magnetic susceptibility measurements over the temperature range 80-300�K have been made for a number of the complexes. In some cases the magnetic moments at room temperature are reduced slightly from the spin-only S = 5/2 value and show θ values of c. 15-50�K. The results can be interpreted in terms of binuclear or polynuclear structures with very small values of the exchange integral J. Comparisons between observed and calculated data are not as good as those shown in related VO2+, NiII, CuII, and FeIII systems for which X-ray crystal structures are known.

Evaluation for Toughness Degradation of 2.25Cr-1Mo Steel Using Magnetic Property Measurement Method

2006 ◽  
Vol 321-323 ◽  
pp. 522-527
Author(s):  
Seung Hoon Nahm ◽  
Jong Seo Park ◽  
In Hyun Chung ◽  
Kwon Sang Ryu ◽  
Am Kee Kim
Keyword(s):  
Magnetic Properties ◽  
Magnetic Property ◽  
Coercive Force ◽  
Magnetic Measurement ◽  
Steel Structure ◽  
Reactor Vessel ◽  
Isothermal Heat Treatment ◽  
Microstructural Changes ◽  
Temperature Levels ◽  
Isothermal Heat Treatments

Many researchers have been interested in the nondestructive measurement methods for examining the microstructural changes and components damage in order to assure the safe operation of steel structure. It has been recognized that the techniques based on magnetic measurement offered a great potential because of high susceptibility to the change of several metallurgical factors. In this study, the effect of isothermal heat treatments, which simulate the microstructural changes observed in reactor vessel material at the service temperature, on the magnetic properties was investigated. 2.25Cr-1Mo steel specimens with several different kinds of aging were prepared by an isothermal heat treatment at three different temperature levels. Magnetic property such as coercive force was measured. The coercive force at room temperature monotonously increased with the extent of degradation of the material. The correlation between the measured magnetic property and the mechanical properties was studied. In addition, the applicability of magnetic properties measurements to the evaluation for toughness degradation of reactor vessel was discussed.

ON SOME ELECTRICAL AND MAGNETIC PROPERTIES OF METALLIC SOLID SOLUTIONS

1956 ◽  
Vol 34 (12A) ◽  
pp. 1190-1211 ◽  
Author(s):  
J. Friedel
Keyword(s):  
Magnetic Properties ◽  
Magnetic Susceptibility ◽  
Electronic Structure ◽  
Thermoelectric Power ◽  
Solid Solutions ◽  
Room Temperature ◽  
Electrical And Magnetic Properties

The resistivity, thermoelectric power, and magnetic susceptibility of metallic solid solutions at room temperature are reviewed, and their relation with their electronic structure emphasized. The special properties of transitional impurities are related to the emptying of their d shells.

STRUCTURAL CHARACTERIZATION, PREPARATION AND MAGNETIC PROPERTIES OF SEVERAL ROOM-TEMPERATURE MAGNETIC OXIDES WITH THE PEROVSKITE-LIKE STRUCTURE

1977 ◽  
Vol 38 (C1) ◽  
pp. C1-95-C1-101 ◽  
Author(s):  
B. BOCHU ◽  
M. N. DESCHIZEAUX ◽  
J. C. JOUBERT ◽  
J. CHENAVAS ◽  
A. COLLOMB ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Structural Characterization ◽  
Room Temperature ◽  
Magnetic Oxides

Photoluminescence and Magnetic Properties of Undoped and (Mn, Co) co-doped ZnO Nanoparticles

2020 ◽  
Vol 16 (4) ◽  
pp. 655-666
Author(s):  
Mona Rekaby
Keyword(s):  
Magnetic Properties ◽  
Zno Nanoparticles ◽  
Room Temperature ◽  
Magnetic Measurements ◽  
Structural Defects ◽  
Ferromagnetic Behavior ◽  
Secondary Phases ◽  
Antiferromagnetic Ordering ◽  
Doped Zno ◽  
Co Doped

Objective: The influence of Manganese (Mn2+) and Cobalt (Co2+) ions doping on the optical and magnetic properties of ZnO nanoparticles was studied. Methods: Nanoparticle samples of type ZnO, Zn0.97Mn0.03O, Zn0.96Mn0.03Co0.01O, Zn0.95Mn0.03 Co0.02O, Zn0.93Mn0.03Co0.04O, and Zn0.91Mn0.03Co0.06O were synthesized using the wet chemical coprecipitation method. Results: X-ray powder diffraction (XRD) patterns revealed that the prepared samples exhibited a single phase of hexagonal wurtzite structure without any existence of secondary phases. Transmission electron microscope (TEM) images clarified that Co doping at high concentrations has the ability to alter the morphologies of the samples from spherical shaped nanoparticles (NPS) to nanorods (NRs) shaped particles. The different vibrational modes of the prepared samples were analyzed through Fourier transform infrared (FTIR) measurements. The optical characteristics and structural defects of the samples were studied through Photoluminescence (PL) spectroscopy. PL results clarified that Mn2+ and Co2+ doping quenched the recombination of electron-hole pairs and enhanced the number of point defects relative to the undoped ZnO sample. Magnetic measurements were carried out at room temperature using a vibrating sample magnetometer (VSM). (Mn, Co) co-doped ZnO samples exhibited a ferromagnetic behavior coupled with paramagnetic and weak diamagnetic contributions. Conclusion: Mn2+ and Co2+ doping enhanced the room temperature Ferromagnetic (RTFM) behavior of ZnO. In addition, the signature for antiferromagnetic ordering between the Co ions was revealed. Moreover, a strong correlation between the magnetic and optical behavior of the (Mn, Co) co-doped ZnO was analyzed.

Effect of Annealing temperature on the Structural and Magnetic Properties of TbxY3-xFe5O12(x = 0.0, 1.0, 2.0) Thin Films Prepared by Sol-Gel Process

2012 ◽  
Vol 501 ◽  
pp. 236-241 ◽  
Author(s):  
Ftema W. Aldbea ◽  
Noor Bahyah Ibrahim ◽  
Mustafa Hj. Abdullah ◽  
Ramadan E. Shaiboub
Keyword(s):  
Thin Films ◽  
Magnetic Properties ◽  
Room Temperature ◽  
Annealing Temperature ◽  
Sol Gel ◽  
Vibrating Sample Magnetometer ◽  
X Ray ◽  
Garnet Phase ◽  
Sol Gel Process ◽  
Amorphous Structures

Thin films nanoparticles TbxY3-xFe5O12 (x=0.0, 1.0, 2.0) were prepared by the sol-gel process followed by annealing process at various annealing temperatures of 700° C, 800° C and 900° C in air for 2 h. The results obtained from X-ray diffractometer (XRD) show that the films annealed below 900°C exhibit peaks of garnet mixed with small amounts of YFeO3 and Fe2O3. Pure garnet phase has been detected in the films annealed at 900°C. Before annealing the films show amorphous structures. The particles sizes measurement using the field emission scanning electron microscope (FE-SEM) showed that the particles sizes increased as the annealing temperature increased. The magnetic properties were measured at room temperature using the vibrating sample magnetometer (VSM). The saturation magnetization (Ms) of the films also increased with the annealing temperature. However, different behavior of coercivity (Hc) has been observed as the annealing temperature was increased.

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