Experimental and Thermodynamic Study of Selected in-Situ Composites from the Fe-Cr-Ni-Mo-C System

AbstractThe aim of the study was to synthesize and characterize the selected in-situ composites from the Fe-Cr-Ni-Mo-C system, additionally strengthened by intermetallic compounds. The project of the alloys was supported by thermodynamic simulations using Calculation of Phase Diagram approach via Thermo-Calc. Selected alloys were synthesized in an arc furnace in a high purity argon atmosphere using a suction casting unit. The studies involved a range of experimental techniques to characterize the alloys in the as-cast state, including optical emission spectrometry, light microscopy, scanning electron microscopy, electron microprobe analysis, X-ray diffraction and microhardness tests. These experimental studies were compared with the Thermo-Calc data and high resolution dilatometry. The results of investigations presented in this paper showed that there is a possibility to introduce intermetallic compounds, such as χ and σ, through modification of the chemical composition of the alloy with respect to Nieq and Creq. It was found that the place of intermetallic compounds precipitation strongly depends on matrix nature. Results presented in this paper may be successfully used to build a systematic knowledge about the group of alloys with a high volume fraction of complex carbides, and high physicochemical properties, additionally strengthened by intermetallic compounds.

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Simultaneous determination of hydride forming elements (As, Bi, Ge, Sb, Se) and Hg in biological and environmental reference materials by electrothermal vaporization–microwave induced plasma-optical emission spectrometry with their in situ trapping in a graphite furnace

Journal of Analytical Atomic Spectrometry ◽

10.1039/b309359j ◽

2003 ◽

Vol 18 (12) ◽

pp. 1415-1425 ◽

Cited By ~ 28

Author(s):

Henryk Matusiewicz ◽

Mariusz Kopras

Keyword(s):

Simultaneous Determination ◽

Graphite Furnace ◽

Optical Emission ◽

Emission Spectrometry ◽

Electrothermal Vaporization ◽

Microwave Induced Plasma ◽

Environmental Reference ◽

Plasma Optical Emission Spectrometry

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Effect of Annealing Conditions on the Dissolution Process of Complex Carbonitrides in a V-Nb-Ti Microalloyed Steel

Materials Science Forum ◽

10.4028/www.scientific.net/msf.941.21 ◽

2018 ◽

Vol 941 ◽

pp. 21-26

Author(s):

Gloria Basanta ◽

Ana L. Rivas ◽

Ervis Díaz ◽

Carlos Parra

Keyword(s):

Inductively Coupled Plasma ◽

Microalloyed Steel ◽

Optical Emission ◽

Dissolution Process ◽

Emission Spectrometry ◽

Inductively Coupled ◽

Annealing Conditions ◽

Plasma Optical Emission Spectrometry

The present work has been undertaken to assess the evolution of dissolution process of large dendritic precipitates in a V-Nb-Ti microalloyed steel. The study was performed by reheating the samples at 1250°C, simulating the industrial reheating practices at laboratory scale and in situ, following industrial profile; afterwards the samples were quenched in 10%NaCl aqueous solution. The characterization of the material was carried out by scanning electron microscopy accompanied with dispersive energy spectrometry, and chemical analysis by inductively coupled plasma optical emission spectrometry. The results showed a partial dissolution of dendritic precipitates. This process ocurred by a progressive dissolving the Nb-rich shells formed over cuboidal particles and primary arm of well-faceted dendritic precipitates, and by fragmentation and spheroidization of secondary branches. These processes gave rise to spherical Nb rich precipitates and cuboidal particles at the reheating conditions used in this study. Both type of particles contain vanadium.

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High Volume Fraction and Length-Diameter Ratio of TiB Short Fiber and TiB2P Reinforce Ti-Based Alloy Composite Coatings by Laser Synthesis In-Situ

Chinese Journal of Lasers ◽

10.3788/cjl201441.0703010 ◽

2014 ◽

Vol 41 (7) ◽

pp. 0703010

Author(s):

林英华 Lin Yinghua ◽

雷永平 Lei Yongping

Keyword(s):

Volume Fraction ◽

Composite Coatings ◽

High Volume ◽

Short Fiber ◽

Diameter Ratio ◽

High Volume Fraction ◽

Alloy Composite ◽

Laser Synthesis

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Real-time depth measurement in glow discharge optical emission spectrometry via differential interferometric profiling

Journal of Analytical Atomic Spectrometry ◽

10.1039/c7ja00146k ◽

2017 ◽

Vol 32 (9) ◽

pp. 1798-1804 ◽

Cited By ~ 11

Author(s):

S. Gaiaschi ◽

S. Richard ◽

P. Chapon ◽

O. Acher

Keyword(s):

Glow Discharge ◽

Real Time ◽

Measurement Technique ◽

Optical Emission ◽

Optical Emission Spectrometry ◽

Emission Spectrometry ◽

Depth Information ◽

Depth Measurement

We developed an in situ measurement technique implemented on a Glow Discharge Optical Emission Spectrometry (GD-OES) instrument, which provides the depth information during the profiling process.

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Dry Sliding Wear Performance of Ni–SiC Composites Developed Through an In Situ Microwave Casting Process

Journal of Tribology ◽

10.1115/1.4047032 ◽

2020 ◽

Vol 142 (10) ◽

Author(s):

Satnam Singh ◽

Dheeraj Gupta ◽

Sarbjeet Kaushal

Keyword(s):

Intermetallic Compounds ◽

Sliding Wear ◽

Volume Fraction ◽

Casting Process ◽

Dry Sliding Wear ◽

Dry Sliding ◽

Sliding Velocity ◽

Uniform Dispersion ◽

Sic Reinforcement

Abstract Metal matrix composites of nickel-based powder reinforced with silicon carbide are processed through a domestic microwave applicator. In situ melting and casting of composites were carried out using microwave energy with average processing time of 25 min. Phase analysis of processed composites revealed the formation of some hard-intermetallic compounds such as nickel silicides (NiSi, Ni2Si, and Ni3Si2) and carbides (Cr3C2 and Cr7C3). Microstructure analysis confirms the favorable growth of equiaxed grains with uniform dispersion of reinforcement and low porosity defects (1.5–1.8%). The formation of hard-intermetallic compounds and the presence of SiC reinforcement led to the increased microhardness of composites. Sliding wear tests under dry sliding conditions with varying load and velocity conditions revealed the formation of stable oxide tribolayers at 1.0 m/s of sliding velocity and 15 N load. Fractography of worn-out samples revealed abrasion of surfaces at the lower load (10 N) condition. However, on increasing the load, the shearing of surfaces due to adhesion, plastic deformations, and surface pullout was observed. At higher loads (20 N) and higher sliding velocities (1.5 m/s), particle pullout and three-body abrasive wear mechanisms were observed. The overall weight loss study revealed that the addition of 5% and 10% volume fraction of SiC reinforcement reduced the wear-rate by 58.9% and 80.6% in comparison to the pure nickel casting at the sliding velocity of 1 m/s and under 15 N load.

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Synthesis of Supported Metal Nanoparticles (Au/TiO2) by the Suspension Impregnation Method

Journal of Composites Science ◽

10.3390/jcs4030089 ◽

2020 ◽

Vol 4 (3) ◽

pp. 89

Author(s):

Carolina Rodríguez-Martínez ◽

Ángel Emilio García-Domínguez ◽

Fernando Guerrero-Robles ◽

Rafael Omar Saavedra-Díaz ◽

Gilberto Torres-Torres ◽

...

Keyword(s):

Titanium Oxide ◽

Inductively Coupled Plasma ◽

Optical Emission ◽

Nitrogen Adsorption ◽

Emission Spectrometry ◽

Particle Sizes ◽

Impregnation Method ◽

Average Pore ◽

Reduction Potentials

This work reports a new technique called “Suspension Impregnation Method” (SiM) as an alternative to the “Incipient Impregnation Method” (IiM) for the synthesis of noble metal (Au) nanoparticles. The SiM was used to synthesize gold nanoparticles supported by titanium oxide and compared with those of IiM. The reactor for the SiM technique was based on the principles of mixing, heat, and mass transfer of the suspension reactors and the metal particle synthesis was processed in situ under the oxidation reduction potentials. Three different conditions were established to observe the effect of pH on the size of the metal particles: acid (HCl), neutral (water) and alkaline (urea). The samples were characterized by nitrogen adsorption, X-Ray Diffraction (XRD), Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES), Thermogravimetric Analysis (TGA)/Differential Thermal Analysis (DTA), Transmission Electron Microscopy (TEM) and CO2 adsorption. The surface area was slightly modified, and the average pore diameter was reduced in all materials. The structure of the titanium oxide was not altered. A deposit of organic material was detected in samples synthesized in alkaline medium for both methods. The pH influenced the formation of conglomerates in IiM and resulted in large particle sizes (3–9 nm). In contrast, an in situ reduction in the species in SiM resulted in smaller particle sizes than IiM (2–3 nm).

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Subgrain rotation during in-situ annealing of Al-6 wt% Ni in the HVEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010011235x ◽

1984 ◽

Vol 42 ◽

pp. 476-477

Author(s):

H. M. Chan ◽

F. J. Humphreys

Keyword(s):

Volume Fraction ◽

Thin Foil ◽

High Volume ◽

Second Phase ◽

Dispersion Parameters ◽

Voltage Electron ◽

High Voltage Electron Microscope ◽

Subgrain Rotation ◽

Alloy Heat

Recently a series of commercial aluminum alloys has been developed (based on eutectic compositions), which contain a high volume fraction (∼10%) of second phase [1,2]. This paper describes the behavior of one such alloy, when thinfoil specimens (75% defd.) were annealed in-situ in the HVEM.The eutectic alloy studied was Al-6 wt% Ni. The alloy heat treatment and particle (Al3Ni) dispersion parameters are given in Table 1. Three-mm discs were punched from as-deformed material. Thin foil specimens were prepared by standard jet polishing techniques. In-situ annealing was carried out in the AEI EM7 high voltage electron microscope at 500 kV, using a platinum ribbon heating stage [3].

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